haven't committed in a while oops. A fuck-ton of HTML stuff

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/AUTHORS.rst

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+Main authors (commit rights to the main repository)
+===================================================
+
+* Chris Glass
+* Diederik van der Boor
+* Charlie Denton
+* Jerome Leclanche
+
+
+Contributors
+=============
+
+* Abel Daniel
+* Adam Chainz
+* Adam Wentz
+* Andrew Ingram (contributed setup.py)
+* Al Johri
+* Alex Alvarez
+* Andrew Dodd
+* Angel Velasquez
+* Austin Matsick
+* Ben Konrath
+* Bert Constantin
+* Bertrand Bordage
+* Chad Shryock
+* Charles Leifer (python 2.4 compatibility)
+* Chris Barna
+* Chris Brantley
+* Christopher Glass
+* David Sanders
+* Éric Araujo
+* Evan Borgstrom
+* Frankie Dintino
+* Gavin Wahl
+* Germán M. Bravo
+* Gonzalo Bustos
+* Gregory Avery-Weir
+* Hugo Osvaldo Barrera
+* Jacob Rief
+* James Murty
+* Jedediah Smith (proxy models support)
+* John Furr
+* Jonas Haag
+* Jonas Obrist
+* Julian Wachholz
+* Kamil Bar
+* Kelsey Gilmore-Innis
+* Kevin Armenat
+* Krzysztof Gromadzki
+* Krzysztof Nazarewski
+* Luis Zárate
+* Marius Lueck
+* Martin Brochhaus
+* Martin Maillard
+* Michael Fladischer
+* Nick Ward
+* Oleg Myltsyn
+* Omer Strumpf
+* Paweł Adamczak
+* Petr Dlouhý
+* Sander van Leeuwen
+* Sobolev Nikita
+* Tadas Dailyda
+* Tai Lee
+* Tomas Peterka
+* Tony Narlock
+* Vail Gold
+
+
+
+Former authors / maintainers
+============================
+
+* Bert Constantin 2009/2010 (Original author, disappeared from the internet :( )

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/INSTALLER

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+pip

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/LICENSE

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+Copyright (c) 2009 or later by the individual contributors.
+Please see the AUTHORS file.
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * The names of the contributors may not be used to endorse or
+      promote products derived from this software without specific
+      prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/METADATA

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+Metadata-Version: 2.1
+Name: django-polymorphic
+Version: 2.1.2
+Summary: Seamless polymorphic inheritance for Django models
+Home-page: https://github.com/django-polymorphic/django-polymorphic
+Author: Bert Constantin
+Author-email: bert.constantin@gmx.de
+Maintainer: Christopher Glass
+Maintainer-email: tribaal@gmail.com
+License: UNKNOWN
+Download-URL: https://github.com/django-polymorphic/django-polymorphic/tarball/master
+Keywords: django,polymorphic
+Platform: UNKNOWN
+Classifier: Development Status :: 5 - Production/Stable
+Classifier: Environment :: Web Environment
+Classifier: Framework :: Django
+Classifier: Framework :: Django :: 1.11
+Classifier: Framework :: Django :: 2.0
+Classifier: Framework :: Django :: 2.1
+Classifier: Framework :: Django :: 2.2
+Classifier: Intended Audience :: Developers
+Classifier: License :: OSI Approved :: BSD License
+Classifier: Operating System :: OS Independent
+Classifier: Programming Language :: Python :: 2.7
+Classifier: Programming Language :: Python :: 3
+Classifier: Programming Language :: Python :: 3.5
+Classifier: Programming Language :: Python :: 3.6
+Classifier: Programming Language :: Python :: 3.7
+Classifier: Topic :: Database
+Requires-Dist: Django (>=1.11)
+
+.. image::  https://travis-ci.org/django-polymorphic/django-polymorphic.svg?branch=master
+    :target: http://travis-ci.org/django-polymorphic/django-polymorphic
+.. image:: https://img.shields.io/pypi/v/django-polymorphic.svg
+    :target: https://pypi.python.org/pypi/django-polymorphic/
+.. image:: https://img.shields.io/codecov/c/github/django-polymorphic/django-polymorphic/master.svg
+    :target: https://codecov.io/github/django-polymorphic/django-polymorphic?branch=master
+.. image:: https://readthedocs.org/projects/django-polymorphic/badge/?version=stable
+    :target: https://django-polymorphic.readthedocs.io/en/stable/
+
+Polymorphic Models for Django
+=============================
+
+Django-polymorphic simplifies using inherited models in Django projects.
+When a query is made at the base model, the inherited model classes are returned.
+
+When we store models that inherit from a ``Project`` model...
+
+.. code-block:: python
+
+    >>> Project.objects.create(topic="Department Party")
+    >>> ArtProject.objects.create(topic="Painting with Tim", artist="T. Turner")
+    >>> ResearchProject.objects.create(topic="Swallow Aerodynamics", supervisor="Dr. Winter")
+
+...and want to retrieve all our projects, the subclassed models are returned!
+
+.. code-block:: python
+
+    >>> Project.objects.all()
+    [ <Project:         id 1, topic "Department Party">,
+      <ArtProject:      id 2, topic "Painting with Tim", artist "T. Turner">,
+      <ResearchProject: id 3, topic "Swallow Aerodynamics", supervisor "Dr. Winter"> ]
+
+Using vanilla Django, we get the base class objects, which is rarely what we wanted:
+
+.. code-block:: python
+
+    >>> Project.objects.all()
+    [ <Project: id 1, topic "Department Party">,
+      <Project: id 2, topic "Painting with Tim">,
+      <Project: id 3, topic "Swallow Aerodynamics"> ]
+
+This also works when the polymorphic model is accessed via
+ForeignKeys, ManyToManyFields or OneToOneFields.
+
+Features
+--------
+
+* Full admin integration.
+* ORM integration:
+
+  * support for ForeignKey, ManyToManyField, OneToOneField descriptors.
+  * Filtering/ordering of inherited models (``ArtProject___artist``).
+  * Filtering model types: ``instance_of(...)`` and ``not_instance_of(...)``
+  * Combining querysets of different models (``qs3 = qs1 | qs2``)
+  * Support for custom user-defined managers.
+* Uses the minumum amount of queries needed to fetch the inherited models.
+* Disabling polymorphic behavior when needed.
+
+While *django-polymorphic* makes subclassed models easy to use in Django,
+we still encourage to use them with caution. Each subclassed model will require
+Django to perform an ``INNER JOIN`` to fetch the model fields from the database.
+While taking this in mind, there are valid reasons for using subclassed models.
+That's what this library is designed for!
+
+The current release of *django-polymorphic* supports Django 1.11, 2.0, 2.1, 2.2 and Python 2.7 and 3.5+ is supported.
+For older Django versions, install *django-polymorphic==1.3*.
+
+For more information, see the `documentation at Read the Docs <https://django-polymorphic.readthedocs.io/>`_.
+
+Installation
+------------
+
+Install using ``pip``\ ...
+
+.. code:: bash
+
+    $ pip install django-polymorphic
+
+License
+=======
+
+Django-polymorphic uses the same license as Django (BSD-like).
+
+

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/RECORD

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venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/WHEEL

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+Generator: bdist_wheel (0.33.4)
+Root-Is-Purelib: true
+Tag: py2-none-any
+Tag: py3-none-any
+

venv/lib/python3.8/site-packages/django_polymorphic-2.1.2.dist-info/top_level.txt

@@ -0,0 +1 @@
+polymorphic

venv/lib/python3.8/site-packages/polymorphic/__init__.py

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+# -*- coding: utf-8 -*-
+"""
+Seamless Polymorphic Inheritance for Django Models
+
+Copyright:
+This code and affiliated files are (C) by Bert Constantin and individual contributors.
+Please see LICENSE and AUTHORS for more information.
+"""
+
+import pkg_resources
+
+try:
+    __version__ = pkg_resources.require("django-polymorphic")[0].version
+except pkg_resources.DistributionNotFound:
+    __version__ = None  # for RTD among others

venv/lib/python3.8/site-packages/polymorphic/admin/__init__.py

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+"""
+ModelAdmin code to display polymorphic models.
+
+The admin consists of a parent admin (which shows in the admin with a list),
+and a child admin (which is used internally to show the edit/delete dialog).
+"""
+# Admins for the regular models
+from .parentadmin import PolymorphicParentModelAdmin  # noqa
+from .childadmin import PolymorphicChildModelAdmin
+from .filters import PolymorphicChildModelFilter
+
+# Utils
+from .forms import PolymorphicModelChoiceForm
+
+# Expose generic admin features too. There is no need to split those
+# as the admin already relies on contenttypes.
+from .generic import GenericPolymorphicInlineModelAdmin  # base class
+from .generic import GenericStackedPolymorphicInline  # stacked inline
+
+# Helpers for the inlines
+from .helpers import PolymorphicInlineSupportMixin  # mixin for the regular model admin!
+from .helpers import PolymorphicInlineAdminForm, PolymorphicInlineAdminFormSet
+
+# Inlines
+from .inlines import PolymorphicInlineModelAdmin  # base class
+from .inlines import StackedPolymorphicInline  # stacked inline
+
+__all__ = (
+    "PolymorphicParentModelAdmin",
+    "PolymorphicChildModelAdmin",
+    "PolymorphicModelChoiceForm",
+    "PolymorphicChildModelFilter",
+    "PolymorphicInlineAdminForm",
+    "PolymorphicInlineAdminFormSet",
+    "PolymorphicInlineSupportMixin",
+    "PolymorphicInlineModelAdmin",
+    "StackedPolymorphicInline",
+    "GenericPolymorphicInlineModelAdmin",
+    "GenericStackedPolymorphicInline",
+)

venv/lib/python3.8/site-packages/polymorphic/admin/childadmin.py

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+"""
+The child admin displays the change/delete view of the subclass model.
+"""
+import inspect
+
+from django.contrib import admin
+from django.urls import resolve
+from django.utils.translation import ugettext_lazy as _
+
+from polymorphic.utils import get_base_polymorphic_model
+
+from ..admin import PolymorphicParentModelAdmin
+
+
+class ParentAdminNotRegistered(RuntimeError):
+    "The admin site for the model is not registered."
+
+
+class PolymorphicChildModelAdmin(admin.ModelAdmin):
+    """
+    The *optional* base class for the admin interface of derived models.
+
+    This base class defines some convenience behavior for the admin interface:
+
+    * It corrects the breadcrumbs in the admin pages.
+    * It adds the base model to the template lookup paths.
+    * It allows to set ``base_form`` so the derived class will automatically include other fields in the form.
+    * It allows to set ``base_fieldsets`` so the derived class will automatically display any extra fields.
+    """
+
+    #: The base model that the class uses (auto-detected if not set explicitly)
+    base_model = None
+
+    #: By setting ``base_form`` instead of ``form``, any subclass fields are automatically added to the form.
+    #: This is useful when your model admin class is inherited by others.
+    base_form = None
+
+    #: By setting ``base_fieldsets`` instead of ``fieldsets``,
+    #: any subclass fields can be automatically added.
+    #: This is useful when your model admin class is inherited by others.
+    base_fieldsets = None
+
+    #: Default title for extra fieldset
+    extra_fieldset_title = _("Contents")
+
+    #: Whether the child admin model should be visible in the admin index page.
+    show_in_index = False
+
+    def __init__(self, model, admin_site, *args, **kwargs):
+        super(PolymorphicChildModelAdmin, self).__init__(
+            model, admin_site, *args, **kwargs
+        )
+
+        if self.base_model is None:
+            self.base_model = get_base_polymorphic_model(model)
+
+    def get_form(self, request, obj=None, **kwargs):
+        # The django admin validation requires the form to have a 'class Meta: model = ..'
+        # attribute, or it will complain that the fields are missing.
+        # However, this enforces all derived ModelAdmin classes to redefine the model as well,
+        # because they need to explicitly set the model again - it will stick with the base model.
+        #
+        # Instead, pass the form unchecked here, because the standard ModelForm will just work.
+        # If the derived class sets the model explicitly, respect that setting.
+        kwargs.setdefault("form", self.base_form or self.form)
+
+        # prevent infinite recursion when this is called from get_subclass_fields
+        if not self.fieldsets and not self.fields:
+            kwargs.setdefault("fields", "__all__")
+
+        return super(PolymorphicChildModelAdmin, self).get_form(request, obj, **kwargs)
+
+    def get_model_perms(self, request):
+        match = resolve(request.path)
+
+        if (
+            not self.show_in_index
+            and match.app_name == "admin"
+            and match.url_name in ("index", "app_list")
+        ):
+            return {"add": False, "change": False, "delete": False}
+        return super(PolymorphicChildModelAdmin, self).get_model_perms(request)
+
+    @property
+    def change_form_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/change_form.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/change_form.html" % app_label,
+            # Added:
+            "admin/%s/%s/change_form.html"
+            % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/change_form.html" % base_app_label,
+            "admin/polymorphic/change_form.html",
+            "admin/change_form.html",
+        ]
+
+    @property
+    def delete_confirmation_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/delete_confirmation.html"
+            % (app_label, opts.object_name.lower()),
+            "admin/%s/delete_confirmation.html" % app_label,
+            # Added:
+            "admin/%s/%s/delete_confirmation.html"
+            % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/delete_confirmation.html" % base_app_label,
+            "admin/polymorphic/delete_confirmation.html",
+            "admin/delete_confirmation.html",
+        ]
+
+    @property
+    def object_history_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/object_history.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/object_history.html" % app_label,
+            # Added:
+            "admin/%s/%s/object_history.html"
+            % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/object_history.html" % base_app_label,
+            "admin/polymorphic/object_history.html",
+            "admin/object_history.html",
+        ]
+
+    def _get_parent_admin(self):
+        # this returns parent admin instance on which to call response_post_save methods
+        parent_model = self.model._meta.get_field("polymorphic_ctype").model
+        if parent_model == self.model:
+            # when parent_model is in among child_models, just return super instance
+            return super(PolymorphicChildModelAdmin, self)
+
+        try:
+            return self.admin_site._registry[parent_model]
+        except KeyError:
+            # Admin is not registered for polymorphic_ctype model, but perhaps it's registered
+            # for a intermediate proxy model, between the parent_model and this model.
+            for klass in inspect.getmro(self.model):
+                if not issubclass(klass, parent_model):
+                    continue  # e.g. found a mixin.
+
+                # Fetch admin instance for model class, see if it's a possible candidate.
+                model_admin = self.admin_site._registry.get(klass)
+                if model_admin is not None and isinstance(
+                    model_admin, PolymorphicParentModelAdmin
+                ):
+                    return model_admin  # Success!
+
+            # If we get this far without returning there is no admin available
+            raise ParentAdminNotRegistered(
+                "No parent admin was registered for a '{0}' model.".format(parent_model)
+            )
+
+    def response_post_save_add(self, request, obj):
+        return self._get_parent_admin().response_post_save_add(request, obj)
+
+    def response_post_save_change(self, request, obj):
+        return self._get_parent_admin().response_post_save_change(request, obj)
+
+    def render_change_form(
+        self, request, context, add=False, change=False, form_url="", obj=None
+    ):
+        context.update({"base_opts": self.base_model._meta})
+        return super(PolymorphicChildModelAdmin, self).render_change_form(
+            request, context, add=add, change=change, form_url=form_url, obj=obj
+        )
+
+    def delete_view(self, request, object_id, context=None):
+        extra_context = {"base_opts": self.base_model._meta}
+        return super(PolymorphicChildModelAdmin, self).delete_view(
+            request, object_id, extra_context
+        )
+
+    def history_view(self, request, object_id, extra_context=None):
+        # Make sure the history view can also display polymorphic breadcrumbs
+        context = {"base_opts": self.base_model._meta}
+        if extra_context:
+            context.update(extra_context)
+        return super(PolymorphicChildModelAdmin, self).history_view(
+            request, object_id, extra_context=context
+        )
+
+    # ---- Extra: improving the form/fieldset default display ----
+
+    def get_base_fieldsets(self, request, obj=None):
+        return self.base_fieldsets
+
+    def get_fieldsets(self, request, obj=None):
+        base_fieldsets = self.get_base_fieldsets(request, obj)
+
+        # If subclass declares fieldsets or fields, this is respected
+        if self.fieldsets or self.fields or not self.base_fieldsets:
+            return super(PolymorphicChildModelAdmin, self).get_fieldsets(request, obj)
+
+        # Have a reasonable default fieldsets,
+        # where the subclass fields are automatically included.
+        other_fields = self.get_subclass_fields(request, obj)
+
+        if other_fields:
+            return (
+                base_fieldsets[0],
+                (self.extra_fieldset_title, {"fields": other_fields}),
+            ) + base_fieldsets[1:]
+        else:
+            return base_fieldsets
+
+    def get_subclass_fields(self, request, obj=None):
+        # Find out how many fields would really be on the form,
+        # if it weren't restricted by declared fields.
+        exclude = list(self.exclude or [])
+        exclude.extend(self.get_readonly_fields(request, obj))
+
+        # By not declaring the fields/form in the base class,
+        # get_form() will populate the form with all available fields.
+        form = self.get_form(request, obj, exclude=exclude)
+        subclass_fields = list(form.base_fields.keys()) + list(
+            self.get_readonly_fields(request, obj)
+        )
+
+        # Find which fields are not part of the common fields.
+        for fieldset in self.get_base_fieldsets(request, obj):
+            for field in fieldset[1]["fields"]:
+                try:
+                    subclass_fields.remove(field)
+                except ValueError:
+                    pass  # field not found in form, Django will raise exception later.
+        return subclass_fields

venv/lib/python3.8/site-packages/polymorphic/admin/filters.py

@@ -0,0 +1,39 @@
+from django.contrib import admin
+from django.core.exceptions import PermissionDenied
+from django.utils.translation import ugettext_lazy as _
+
+
+class PolymorphicChildModelFilter(admin.SimpleListFilter):
+    """
+    An admin list filter for the PolymorphicParentModelAdmin which enables
+    filtering by its child models.
+
+    This can be used in the parent admin:
+
+    .. code-block:: python
+
+        list_filter = (PolymorphicChildModelFilter,)
+    """
+
+    title = _("Type")
+    parameter_name = "polymorphic_ctype"
+
+    def lookups(self, request, model_admin):
+        return model_admin.get_child_type_choices(request, "change")
+
+    def queryset(self, request, queryset):
+        try:
+            value = int(self.value())
+        except TypeError:
+            value = None
+        if value:
+            # ensure the content type is allowed
+            for choice_value, _ in self.lookup_choices:
+                if choice_value == value:
+                    return queryset.filter(polymorphic_ctype_id=choice_value)
+            raise PermissionDenied(
+                'Invalid ContentType "{0}". It must be registered as child model.'.format(
+                    value
+                )
+            )
+        return queryset

venv/lib/python3.8/site-packages/polymorphic/admin/forms.py

@@ -0,0 +1,21 @@
+from django import forms
+from django.contrib.admin.widgets import AdminRadioSelect
+from django.utils.translation import ugettext_lazy as _
+
+
+class PolymorphicModelChoiceForm(forms.Form):
+    """
+    The default form for the ``add_type_form``. Can be overwritten and replaced.
+    """
+
+    #: Define the label for the radiofield
+    type_label = _("Type")
+
+    ct_id = forms.ChoiceField(
+        label=type_label, widget=AdminRadioSelect(attrs={"class": "radiolist"})
+    )
+
+    def __init__(self, *args, **kwargs):
+        # Allow to easily redefine the label (a commonly expected usecase)
+        super(PolymorphicModelChoiceForm, self).__init__(*args, **kwargs)
+        self.fields["ct_id"].label = self.type_label

venv/lib/python3.8/site-packages/polymorphic/admin/generic.py

@@ -0,0 +1,74 @@
+from django.contrib.contenttypes.admin import GenericInlineModelAdmin
+from django.contrib.contenttypes.models import ContentType
+from django.utils.functional import cached_property
+
+from polymorphic.formsets import (
+    BaseGenericPolymorphicInlineFormSet,
+    GenericPolymorphicFormSetChild,
+    polymorphic_child_forms_factory,
+)
+
+from .inlines import PolymorphicInlineModelAdmin
+
+
+class GenericPolymorphicInlineModelAdmin(
+    PolymorphicInlineModelAdmin, GenericInlineModelAdmin
+):
+    """
+    Base class for variation of inlines based on generic foreign keys.
+    """
+
+    #: The formset class
+    formset = BaseGenericPolymorphicInlineFormSet
+
+    def get_formset(self, request, obj=None, **kwargs):
+        """
+        Construct the generic inline formset class.
+        """
+        # Construct the FormSet class. This is almost the same as parent version,
+        # except that a different super is called so generic_inlineformset_factory() is used.
+        # NOTE that generic_inlineformset_factory() also makes sure the GFK fields are excluded in the form.
+        FormSet = GenericInlineModelAdmin.get_formset(self, request, obj=obj, **kwargs)
+
+        FormSet.child_forms = polymorphic_child_forms_factory(
+            formset_children=self.get_formset_children(request, obj=obj)
+        )
+        return FormSet
+
+    class Child(PolymorphicInlineModelAdmin.Child):
+        """
+        Variation for generic inlines.
+        """
+
+        # Make sure that the GFK fields are excluded from the child forms
+        formset_child = GenericPolymorphicFormSetChild
+        ct_field = "content_type"
+        ct_fk_field = "object_id"
+
+        @cached_property
+        def content_type(self):
+            """
+            Expose the ContentType that the child relates to.
+            This can be used for the ``polymorphic_ctype`` field.
+            """
+            return ContentType.objects.get_for_model(
+                self.model, for_concrete_model=False
+            )
+
+        def get_formset_child(self, request, obj=None, **kwargs):
+            # Similar to GenericInlineModelAdmin.get_formset(),
+            # make sure the GFK is automatically excluded from the form
+            defaults = {"ct_field": self.ct_field, "fk_field": self.ct_fk_field}
+            defaults.update(kwargs)
+            return super(
+                GenericPolymorphicInlineModelAdmin.Child, self
+            ).get_formset_child(request, obj=obj, **defaults)
+
+
+class GenericStackedPolymorphicInline(GenericPolymorphicInlineModelAdmin):
+    """
+    The stacked layout for generic inlines.
+    """
+
+    #: The default template to use.
+    template = "admin/polymorphic/edit_inline/stacked.html"

venv/lib/python3.8/site-packages/polymorphic/admin/helpers.py

@@ -0,0 +1,146 @@
+"""
+Rendering utils for admin forms;
+
+This makes sure that admin fieldsets/layout settings are exported to the template.
+"""
+import json
+
+from django.contrib.admin.helpers import AdminField, InlineAdminForm, InlineAdminFormSet
+from django.utils.encoding import force_text
+from django.utils.text import capfirst
+from django.utils.translation import ugettext
+
+from polymorphic.formsets import BasePolymorphicModelFormSet
+
+
+class PolymorphicInlineAdminForm(InlineAdminForm):
+    """
+    Expose the admin configuration for a form
+    """
+
+    def polymorphic_ctype_field(self):
+        return AdminField(self.form, "polymorphic_ctype", False)
+
+    @property
+    def is_empty(self):
+        return "__prefix__" in self.form.prefix
+
+
+class PolymorphicInlineAdminFormSet(InlineAdminFormSet):
+    """
+    Internally used class to expose the formset in the template.
+    """
+
+    def __init__(self, *args, **kwargs):
+        # Assigned later via PolymorphicInlineSupportMixin later.
+        self.request = kwargs.pop("request", None)
+        self.obj = kwargs.pop("obj", None)
+        super(PolymorphicInlineAdminFormSet, self).__init__(*args, **kwargs)
+
+    def __iter__(self):
+        """
+        Output all forms using the proper subtype settings.
+        """
+        for form, original in zip(
+            self.formset.initial_forms, self.formset.get_queryset()
+        ):
+            # Output the form
+            model = original.get_real_instance_class()
+            child_inline = self.opts.get_child_inline_instance(model)
+            view_on_site_url = self.opts.get_view_on_site_url(original)
+
+            yield PolymorphicInlineAdminForm(
+                formset=self.formset,
+                form=form,
+                fieldsets=self.get_child_fieldsets(child_inline),
+                prepopulated_fields=self.get_child_prepopulated_fields(child_inline),
+                original=original,
+                readonly_fields=self.get_child_readonly_fields(child_inline),
+                model_admin=child_inline,
+                view_on_site_url=view_on_site_url,
+            )
+
+        # Extra rows, and empty prefixed forms.
+        for form in self.formset.extra_forms + self.formset.empty_forms:
+            model = form._meta.model
+            child_inline = self.opts.get_child_inline_instance(model)
+            yield PolymorphicInlineAdminForm(
+                formset=self.formset,
+                form=form,
+                fieldsets=self.get_child_fieldsets(child_inline),
+                prepopulated_fields=self.get_child_prepopulated_fields(child_inline),
+                original=None,
+                readonly_fields=self.get_child_readonly_fields(child_inline),
+                model_admin=child_inline,
+            )
+
+    def get_child_fieldsets(self, child_inline):
+        return list(child_inline.get_fieldsets(self.request, self.obj) or ())
+
+    def get_child_readonly_fields(self, child_inline):
+        return list(child_inline.get_readonly_fields(self.request, self.obj))
+
+    def get_child_prepopulated_fields(self, child_inline):
+        fields = self.prepopulated_fields.copy()
+        fields.update(child_inline.get_prepopulated_fields(self.request, self.obj))
+        return fields
+
+    def inline_formset_data(self):
+        """
+        A JavaScript data structure for the JavaScript code
+        This overrides the default Django version to add the ``childTypes`` data.
+        """
+        verbose_name = self.opts.verbose_name
+        return json.dumps(
+            {
+                "name": "#%s" % self.formset.prefix,
+                "options": {
+                    "prefix": self.formset.prefix,
+                    "addText": ugettext("Add another %(verbose_name)s")
+                    % {"verbose_name": capfirst(verbose_name)},
+                    "childTypes": [
+                        {
+                            "type": model._meta.model_name,
+                            "name": force_text(model._meta.verbose_name),
+                        }
+                        for model in self.formset.child_forms.keys()
+                    ],
+                    "deleteText": ugettext("Remove"),
+                },
+            }
+        )
+
+
+class PolymorphicInlineSupportMixin(object):
+    """
+    A Mixin to add to the regular admin, so it can work with our polymorphic inlines.
+
+    This mixin needs to be included in the admin that hosts the ``inlines``.
+    It makes sure the generated admin forms have different fieldsets/fields
+    depending on the polymorphic type of the form instance.
+
+    This is achieved by overwriting :func:`get_inline_formsets` to return
+    an :class:`PolymorphicInlineAdminFormSet` instead of a standard Django
+    :class:`~django.contrib.admin.helpers.InlineAdminFormSet` for the polymorphic formsets.
+    """
+
+    def get_inline_formsets(
+        self, request, formsets, inline_instances, obj=None, *args, **kwargs
+    ):
+        """
+        Overwritten version to produce the proper admin wrapping for the
+        polymorphic inline formset. This fixes the media and form appearance
+        of the inline polymorphic models.
+        """
+        inline_admin_formsets = super(
+            PolymorphicInlineSupportMixin, self
+        ).get_inline_formsets(request, formsets, inline_instances, obj=obj)
+
+        for admin_formset in inline_admin_formsets:
+            if isinstance(admin_formset.formset, BasePolymorphicModelFormSet):
+                # This is a polymorphic formset, which belongs to our inline.
+                # Downcast the admin wrapper that generates the form fields.
+                admin_formset.__class__ = PolymorphicInlineAdminFormSet
+                admin_formset.request = request
+                admin_formset.obj = obj
+        return inline_admin_formsets

venv/lib/python3.8/site-packages/polymorphic/admin/inlines.py

@@ -0,0 +1,275 @@
+"""
+Django Admin support for polymorphic inlines.
+
+Each row in the inline can correspond with a different subclass.
+"""
+from functools import partial
+
+from django.conf import settings
+from django.contrib.admin.options import InlineModelAdmin
+from django.contrib.admin.utils import flatten_fieldsets
+from django.core.exceptions import ImproperlyConfigured
+from django.forms import Media
+
+from polymorphic.formsets import (
+    BasePolymorphicInlineFormSet,
+    PolymorphicFormSetChild,
+    UnsupportedChildType,
+    polymorphic_child_forms_factory,
+)
+from polymorphic.formsets.utils import add_media
+
+from .helpers import PolymorphicInlineSupportMixin
+
+
+class PolymorphicInlineModelAdmin(InlineModelAdmin):
+    """
+    A polymorphic inline, where each formset row can be a different form.
+
+    Note that:
+
+    * Permissions are only checked on the base model.
+    * The child inlines can't override the base model fields, only this parent inline can do that.
+    """
+
+    formset = BasePolymorphicInlineFormSet
+
+    #: The extra media to add for the polymorphic inlines effect.
+    #: This can be redefined for subclasses.
+    polymorphic_media = Media(
+        js=(
+            "admin/js/vendor/jquery/jquery{}.js".format(
+                "" if settings.DEBUG else ".min"
+            ),
+            "admin/js/jquery.init.js",
+            "polymorphic/js/polymorphic_inlines.js",
+        ),
+        css={"all": ("polymorphic/css/polymorphic_inlines.css",)},
+    )
+
+    #: The extra forms to show
+    #: By default there are no 'extra' forms as the desired type is unknown.
+    #: Instead, add each new item using JavaScript that first offers a type-selection.
+    extra = 0
+
+    #: Inlines for all model sub types that can be displayed in this inline.
+    #: Each row is a :class:`PolymorphicInlineModelAdmin.Child`
+    child_inlines = ()
+
+    def __init__(self, parent_model, admin_site):
+        super(PolymorphicInlineModelAdmin, self).__init__(parent_model, admin_site)
+
+        # Extra check to avoid confusion
+        # While we could monkeypatch the admin here, better stay explicit.
+        parent_admin = admin_site._registry.get(parent_model, None)
+        if parent_admin is not None:  # Can be None during check
+            if not isinstance(parent_admin, PolymorphicInlineSupportMixin):
+                raise ImproperlyConfigured(
+                    "To use polymorphic inlines, add the `PolymorphicInlineSupportMixin` mixin "
+                    "to the ModelAdmin that hosts the inline."
+                )
+
+        # While the inline is created per request, the 'request' object is not known here.
+        # Hence, creating all child inlines unconditionally, without checking permissions.
+        self.child_inline_instances = self.get_child_inline_instances()
+
+        # Create a lookup table
+        self._child_inlines_lookup = {}
+        for child_inline in self.child_inline_instances:
+            self._child_inlines_lookup[child_inline.model] = child_inline
+
+    def get_child_inline_instances(self):
+        """
+        :rtype List[PolymorphicInlineModelAdmin.Child]
+        """
+        instances = []
+        for ChildInlineType in self.child_inlines:
+            instances.append(ChildInlineType(parent_inline=self))
+        return instances
+
+    def get_child_inline_instance(self, model):
+        """
+        Find the child inline for a given model.
+
+        :rtype: PolymorphicInlineModelAdmin.Child
+        """
+        try:
+            return self._child_inlines_lookup[model]
+        except KeyError:
+            raise UnsupportedChildType(
+                "Model '{0}' not found in child_inlines".format(model.__name__)
+            )
+
+    def get_formset(self, request, obj=None, **kwargs):
+        """
+        Construct the inline formset class.
+
+        This passes all class attributes to the formset.
+
+        :rtype: type
+        """
+        # Construct the FormSet class
+        FormSet = super(PolymorphicInlineModelAdmin, self).get_formset(
+            request, obj=obj, **kwargs
+        )
+
+        # Instead of completely redefining super().get_formset(), we use
+        # the regular inlineformset_factory(), and amend that with our extra bits.
+        # This code line is the essence of what polymorphic_inlineformset_factory() does.
+        FormSet.child_forms = polymorphic_child_forms_factory(
+            formset_children=self.get_formset_children(request, obj=obj)
+        )
+        return FormSet
+
+    def get_formset_children(self, request, obj=None):
+        """
+        The formset 'children' provide the details for all child models that are part of this formset.
+        It provides a stripped version of the modelform/formset factory methods.
+        """
+        formset_children = []
+        for child_inline in self.child_inline_instances:
+            # TODO: the children can be limited here per request based on permissions.
+            formset_children.append(child_inline.get_formset_child(request, obj=obj))
+        return formset_children
+
+    def get_fieldsets(self, request, obj=None):
+        """
+        Hook for specifying fieldsets.
+        """
+        if self.fieldsets:
+            return self.fieldsets
+        else:
+            return []  # Avoid exposing fields to the child
+
+    def get_fields(self, request, obj=None):
+        if self.fields:
+            return self.fields
+        else:
+            return []  # Avoid exposing fields to the child
+
+    @property
+    def media(self):
+        # The media of the inline focuses on the admin settings,
+        # whether to expose the scripts for filter_horizontal etc..
+        # The admin helper exposes the inline + formset media.
+        base_media = super(PolymorphicInlineModelAdmin, self).media
+        all_media = Media()
+        add_media(all_media, base_media)
+
+        # Add all media of the child inline instances
+        for child_instance in self.child_inline_instances:
+            child_media = child_instance.media
+
+            # Avoid adding the same media object again and again
+            if (
+                child_media._css != base_media._css
+                and child_media._js != base_media._js
+            ):
+                add_media(all_media, child_media)
+
+        add_media(all_media, self.polymorphic_media)
+
+        return all_media
+
+    class Child(InlineModelAdmin):
+        """
+        The child inline; which allows configuring the admin options
+        for the child appearance.
+
+        Note that not all options will be honored by the parent, notably the formset options:
+        * :attr:`extra`
+        * :attr:`min_num`
+        * :attr:`max_num`
+
+        The model form options however, will all be read.
+        """
+
+        formset_child = PolymorphicFormSetChild
+        extra = 0  # TODO: currently unused for the children.
+
+        def __init__(self, parent_inline):
+            self.parent_inline = parent_inline
+            super(PolymorphicInlineModelAdmin.Child, self).__init__(
+                parent_inline.parent_model, parent_inline.admin_site
+            )
+
+        def get_formset(self, request, obj=None, **kwargs):
+            # The child inline is only used to construct the form,
+            # and allow to override the form field attributes.
+            # The formset is created by the parent inline.
+            raise RuntimeError("The child get_formset() is not used.")
+
+        def get_fields(self, request, obj=None):
+            if self.fields:
+                return self.fields
+
+            # Standard Django logic, use the form to determine the fields.
+            # The form needs to pass through all factory logic so all 'excludes' are set as well.
+            # Default Django does: form = self.get_formset(request, obj, fields=None).form
+            # Use 'fields=None' avoids recursion in the field autodetection.
+            form = self.get_formset_child(request, obj, fields=None).get_form()
+            return list(form.base_fields) + list(self.get_readonly_fields(request, obj))
+
+        def get_formset_child(self, request, obj=None, **kwargs):
+            """
+            Return the formset child that the parent inline can use to represent us.
+
+            :rtype: PolymorphicFormSetChild
+            """
+            # Similar to the normal get_formset(), the caller may pass fields to override the defaults settings
+            # in the inline. In Django's GenericInlineModelAdmin.get_formset() this is also used in the same way,
+            # to make sure the 'exclude' also contains the GFK fields.
+            #
+            # Hence this code is almost identical to InlineModelAdmin.get_formset()
+            # and GenericInlineModelAdmin.get_formset()
+            #
+            # Transfer the local inline attributes to the formset child,
+            # this allows overriding settings.
+            if "fields" in kwargs:
+                fields = kwargs.pop("fields")
+            else:
+                fields = flatten_fieldsets(self.get_fieldsets(request, obj))
+
+            if self.exclude is None:
+                exclude = []
+            else:
+                exclude = list(self.exclude)
+
+            exclude.extend(self.get_readonly_fields(request, obj))
+            # Add forcefully, as Django 1.10 doesn't include readonly fields.
+            exclude.append("polymorphic_ctype")
+
+            if (
+                self.exclude is None
+                and hasattr(self.form, "_meta")
+                and self.form._meta.exclude
+            ):
+                # Take the custom ModelForm's Meta.exclude into account only if the
+                # InlineModelAdmin doesn't define its own.
+                exclude.extend(self.form._meta.exclude)
+
+            # can_delete = self.can_delete and self.has_delete_permission(request, obj)
+            defaults = {
+                "form": self.form,
+                "fields": fields,
+                "exclude": exclude or None,
+                "formfield_callback": partial(
+                    self.formfield_for_dbfield, request=request
+                ),
+            }
+            defaults.update(kwargs)
+
+            # This goes through the same logic that get_formset() calls
+            # by passing the inline class attributes to modelform_factory()
+            FormSetChildClass = self.formset_child
+            return FormSetChildClass(self.model, **defaults)
+
+
+class StackedPolymorphicInline(PolymorphicInlineModelAdmin):
+    """
+    Stacked inline for django-polymorphic models.
+    Since tabular doesn't make much sense with changed fields, just offer this one.
+    """
+
+    #: The default template to use.
+    template = "admin/polymorphic/edit_inline/stacked.html"

venv/lib/python3.8/site-packages/polymorphic/admin/parentadmin.py

@@ -0,0 +1,406 @@
+"""
+The parent admin displays the list view of the base model.
+"""
+import sys
+
+from django.contrib import admin
+from django.contrib.admin.helpers import AdminErrorList, AdminForm
+from django.contrib.admin.templatetags.admin_urls import add_preserved_filters
+from django.contrib.contenttypes.models import ContentType
+from django.core.exceptions import ImproperlyConfigured, PermissionDenied
+from django.db import models
+from django.http import Http404, HttpResponseRedirect
+from django.template.response import TemplateResponse
+from django.utils.encoding import force_text
+from django.utils.http import urlencode
+from django.utils.safestring import mark_safe
+from django.utils.translation import ugettext_lazy as _
+
+from polymorphic.utils import get_base_polymorphic_model
+
+from .forms import PolymorphicModelChoiceForm
+
+try:
+    # Django 2.0+
+    from django.urls import URLResolver
+except ImportError:
+    # Django < 2.0
+    from django.urls import RegexURLResolver as URLResolver
+
+
+if sys.version_info[0] >= 3:
+    long = int
+
+
+class RegistrationClosed(RuntimeError):
+    "The admin model can't be registered anymore at this point."
+
+
+class ChildAdminNotRegistered(RuntimeError):
+    "The admin site for the model is not registered."
+
+
+class PolymorphicParentModelAdmin(admin.ModelAdmin):
+    """
+    A admin interface that can displays different change/delete pages, depending on the polymorphic model.
+    To use this class, one attribute need to be defined:
+
+    * :attr:`child_models` should be a list models.
+
+    Alternatively, the following methods can be implemented:
+
+    * :func:`get_child_models` should return a list of models.
+    * optionally, :func:`get_child_type_choices` can be overwritten to refine the choices for the add dialog.
+
+    This class needs to be inherited by the model admin base class that is registered in the site.
+    The derived models should *not* register the ModelAdmin, but instead it should be returned by :func:`get_child_models`.
+    """
+
+    #: The base model that the class uses (auto-detected if not set explicitly)
+    base_model = None
+
+    #: The child models that should be displayed
+    child_models = None
+
+    #: Whether the list should be polymorphic too, leave to ``False`` to optimize
+    polymorphic_list = False
+
+    add_type_template = None
+    add_type_form = PolymorphicModelChoiceForm
+
+    #: The regular expression to filter the primary key in the URL.
+    #: This accepts only numbers as defensive measure against catch-all URLs.
+    #: If your primary key consists of string values, update this regular expression.
+    pk_regex = r"(\d+|__fk__)"
+
+    def __init__(self, model, admin_site, *args, **kwargs):
+        super(PolymorphicParentModelAdmin, self).__init__(
+            model, admin_site, *args, **kwargs
+        )
+        self._is_setup = False
+
+        if self.base_model is None:
+            self.base_model = get_base_polymorphic_model(model)
+
+    def _lazy_setup(self):
+        if self._is_setup:
+            return
+
+        self._child_models = self.get_child_models()
+
+        # Make absolutely sure that the child models don't use the old 0.9 format,
+        # as of polymorphic 1.4 this deprecated configuration is no longer supported.
+        # Instead, register the child models in the admin too.
+        if self._child_models and not issubclass(self._child_models[0], models.Model):
+            raise ImproperlyConfigured(
+                "Since django-polymorphic 1.4, the `child_models` attribute "
+                "and `get_child_models()` method should be a list of models only.\n"
+                "The model-admin class should be registered in the regular Django admin."
+            )
+
+        self._child_admin_site = self.admin_site
+        self._is_setup = True
+
+    def register_child(self, model, model_admin):
+        """
+        Register a model with admin to display.
+        """
+        # After the get_urls() is called, the URLs of the child model can't be exposed anymore to the Django URLconf,
+        # which also means that a "Save and continue editing" button won't work.
+        if self._is_setup:
+            raise RegistrationClosed(
+                "The admin model can't be registered anymore at this point."
+            )
+
+        if not issubclass(model, self.base_model):
+            raise TypeError(
+                "{0} should be a subclass of {1}".format(
+                    model.__name__, self.base_model.__name__
+                )
+            )
+        if not issubclass(model_admin, admin.ModelAdmin):
+            raise TypeError(
+                "{0} should be a subclass of {1}".format(
+                    model_admin.__name__, admin.ModelAdmin.__name__
+                )
+            )
+
+        self._child_admin_site.register(model, model_admin)
+
+    def get_child_models(self):
+        """
+        Return the derived model classes which this admin should handle.
+        This should return a list of tuples, exactly like :attr:`child_models` is.
+
+        The model classes can be retrieved as ``base_model.__subclasses__()``,
+        a setting in a config file, or a query of a plugin registration system at your option
+        """
+        if self.child_models is None:
+            raise NotImplementedError("Implement get_child_models() or child_models")
+
+        return self.child_models
+
+    def get_child_type_choices(self, request, action):
+        """
+        Return a list of polymorphic types for which the user has the permission to perform the given action.
+        """
+        self._lazy_setup()
+        choices = []
+        for model in self.get_child_models():
+            perm_function_name = "has_{0}_permission".format(action)
+            model_admin = self._get_real_admin_by_model(model)
+            perm_function = getattr(model_admin, perm_function_name)
+            if not perm_function(request):
+                continue
+            ct = ContentType.objects.get_for_model(model, for_concrete_model=False)
+            choices.append((ct.id, model._meta.verbose_name))
+        return choices
+
+    def _get_real_admin(self, object_id, super_if_self=True):
+        try:
+            obj = (
+                self.model.objects.non_polymorphic()
+                .values("polymorphic_ctype")
+                .get(pk=object_id)
+            )
+        except self.model.DoesNotExist:
+            raise Http404
+        return self._get_real_admin_by_ct(
+            obj["polymorphic_ctype"], super_if_self=super_if_self
+        )
+
+    def _get_real_admin_by_ct(self, ct_id, super_if_self=True):
+        try:
+            ct = ContentType.objects.get_for_id(ct_id)
+        except ContentType.DoesNotExist as e:
+            raise Http404(e)  # Handle invalid GET parameters
+
+        model_class = ct.model_class()
+        if not model_class:
+            # Handle model deletion
+            raise Http404("No model found for '{0}.{1}'.".format(*ct.natural_key()))
+
+        return self._get_real_admin_by_model(model_class, super_if_self=super_if_self)
+
+    def _get_real_admin_by_model(self, model_class, super_if_self=True):
+        # In case of a ?ct_id=### parameter, the view is already checked for permissions.
+        # Hence, make sure this is a derived object, or risk exposing other admin interfaces.
+        if model_class not in self._child_models:
+            raise PermissionDenied(
+                "Invalid model '{0}', it must be registered as child model.".format(
+                    model_class
+                )
+            )
+
+        try:
+            # HACK: the only way to get the instance of an model admin,
+            # is to read the registry of the AdminSite.
+            real_admin = self._child_admin_site._registry[model_class]
+        except KeyError:
+            raise ChildAdminNotRegistered(
+                "No child admin site was registered for a '{0}' model.".format(
+                    model_class
+                )
+            )
+
+        if super_if_self and real_admin is self:
+            return super(PolymorphicParentModelAdmin, self)
+        else:
+            return real_admin
+
+    def get_queryset(self, request):
+        # optimize the list display.
+        qs = super(PolymorphicParentModelAdmin, self).get_queryset(request)
+        if not self.polymorphic_list:
+            qs = qs.non_polymorphic()
+        return qs
+
+    def add_view(self, request, form_url="", extra_context=None):
+        """Redirect the add view to the real admin."""
+        ct_id = int(request.GET.get("ct_id", 0))
+        if not ct_id:
+            # Display choices
+            return self.add_type_view(request)
+        else:
+            real_admin = self._get_real_admin_by_ct(ct_id)
+            # rebuild form_url, otherwise libraries below will override it.
+            form_url = add_preserved_filters(
+                {
+                    "preserved_filters": urlencode({"ct_id": ct_id}),
+                    "opts": self.model._meta,
+                },
+                form_url,
+            )
+            return real_admin.add_view(request, form_url, extra_context)
+
+    def change_view(self, request, object_id, *args, **kwargs):
+        """Redirect the change view to the real admin."""
+        real_admin = self._get_real_admin(object_id)
+        return real_admin.change_view(request, object_id, *args, **kwargs)
+
+    def changeform_view(self, request, object_id=None, *args, **kwargs):
+        # The `changeform_view` is available as of Django 1.7, combining the add_view and change_view.
+        # As it's directly called by django-reversion, this method is also overwritten to make sure it
+        # also redirects to the child admin.
+        if object_id:
+            real_admin = self._get_real_admin(object_id)
+            return real_admin.changeform_view(request, object_id, *args, **kwargs)
+        else:
+            # Add view. As it should already be handled via `add_view`, this means something custom is done here!
+            return super(PolymorphicParentModelAdmin, self).changeform_view(
+                request, object_id, *args, **kwargs
+            )
+
+    def history_view(self, request, object_id, extra_context=None):
+        """Redirect the history view to the real admin."""
+        real_admin = self._get_real_admin(object_id)
+        return real_admin.history_view(request, object_id, extra_context=extra_context)
+
+    def delete_view(self, request, object_id, extra_context=None):
+        """Redirect the delete view to the real admin."""
+        real_admin = self._get_real_admin(object_id)
+        return real_admin.delete_view(request, object_id, extra_context)
+
+    def get_preserved_filters(self, request):
+        if "_changelist_filters" in request.GET:
+            request.GET = request.GET.copy()
+            filters = request.GET.get("_changelist_filters")
+            f = filters.split("&")
+            for x in f:
+                c = x.split("=")
+                request.GET[c[0]] = c[1]
+            del request.GET["_changelist_filters"]
+        return super(PolymorphicParentModelAdmin, self).get_preserved_filters(request)
+
+    def get_urls(self):
+        """
+        Expose the custom URLs for the subclasses and the URL resolver.
+        """
+        urls = super(PolymorphicParentModelAdmin, self).get_urls()
+
+        # At this point. all admin code needs to be known.
+        self._lazy_setup()
+
+        return urls
+
+    def subclass_view(self, request, path):
+        """
+        Forward any request to a custom view of the real admin.
+        """
+        ct_id = int(request.GET.get("ct_id", 0))
+        if not ct_id:
+            # See if the path started with an ID.
+            try:
+                pos = path.find("/")
+                if pos == -1:
+                    object_id = long(path)
+                else:
+                    object_id = long(path[0:pos])
+            except ValueError:
+                raise Http404(
+                    "No ct_id parameter, unable to find admin subclass for path '{0}'.".format(
+                        path
+                    )
+                )
+
+            ct_id = self.model.objects.values_list(
+                "polymorphic_ctype_id", flat=True
+            ).get(pk=object_id)
+
+        real_admin = self._get_real_admin_by_ct(ct_id)
+        resolver = URLResolver("^", real_admin.urls)
+        resolvermatch = resolver.resolve(path)  # May raise Resolver404
+        if not resolvermatch:
+            raise Http404("No match for path '{0}' in admin subclass.".format(path))
+
+        return resolvermatch.func(request, *resolvermatch.args, **resolvermatch.kwargs)
+
+    def add_type_view(self, request, form_url=""):
+        """
+        Display a choice form to select which page type to add.
+        """
+        if not self.has_add_permission(request):
+            raise PermissionDenied
+
+        extra_qs = ""
+        if request.META["QUERY_STRING"]:
+            # QUERY_STRING is bytes in Python 3, using force_text() to decode it as string.
+            # See QueryDict how Django deals with that.
+            extra_qs = "&{0}".format(force_text(request.META["QUERY_STRING"]))
+
+        choices = self.get_child_type_choices(request, "add")
+        if len(choices) == 1:
+            return HttpResponseRedirect("?ct_id={0}{1}".format(choices[0][0], extra_qs))
+
+        # Create form
+        form = self.add_type_form(
+            data=request.POST if request.method == "POST" else None,
+            initial={"ct_id": choices[0][0]},
+        )
+        form.fields["ct_id"].choices = choices
+
+        if form.is_valid():
+            return HttpResponseRedirect(
+                "?ct_id={0}{1}".format(form.cleaned_data["ct_id"], extra_qs)
+            )
+
+        # Wrap in all admin layout
+        fieldsets = ((None, {"fields": ("ct_id",)}),)
+        adminForm = AdminForm(form, fieldsets, {}, model_admin=self)
+        media = self.media + adminForm.media
+        opts = self.model._meta
+
+        context = {
+            "title": _("Add %s") % force_text(opts.verbose_name),
+            "adminform": adminForm,
+            "is_popup": ("_popup" in request.POST or "_popup" in request.GET),
+            "media": mark_safe(media),
+            "errors": AdminErrorList(form, ()),
+            "app_label": opts.app_label,
+        }
+        return self.render_add_type_form(request, context, form_url)
+
+    def render_add_type_form(self, request, context, form_url=""):
+        """
+        Render the page type choice form.
+        """
+        opts = self.model._meta
+        app_label = opts.app_label
+        context.update(
+            {
+                "has_change_permission": self.has_change_permission(request),
+                "form_url": mark_safe(form_url),
+                "opts": opts,
+                "add": True,
+                "save_on_top": self.save_on_top,
+            }
+        )
+
+        templates = self.add_type_template or [
+            "admin/%s/%s/add_type_form.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/add_type_form.html" % app_label,
+            "admin/polymorphic/add_type_form.html",  # added default here
+            "admin/add_type_form.html",
+        ]
+
+        request.current_app = self.admin_site.name
+        return TemplateResponse(request, templates, context)
+
+    @property
+    def change_list_template(self):
+        opts = self.model._meta
+        app_label = opts.app_label
+
+        # Pass the base options
+        base_opts = self.base_model._meta
+        base_app_label = base_opts.app_label
+
+        return [
+            "admin/%s/%s/change_list.html" % (app_label, opts.object_name.lower()),
+            "admin/%s/change_list.html" % app_label,
+            # Added base class:
+            "admin/%s/%s/change_list.html"
+            % (base_app_label, base_opts.object_name.lower()),
+            "admin/%s/change_list.html" % base_app_label,
+            "admin/change_list.html",
+        ]

venv/lib/python3.8/site-packages/polymorphic/base.py

@@ -0,0 +1,219 @@
+# -*- coding: utf-8 -*-
+"""
+PolymorphicModel Meta Class
+"""
+from __future__ import absolute_import
+
+import inspect
+import os
+import sys
+import warnings
+
+import django
+from django.core.exceptions import ImproperlyConfigured
+from django.db import models
+from django.db.models.base import ModelBase
+from django.db.models.manager import ManagerDescriptor
+
+from .managers import PolymorphicManager
+from .query import PolymorphicQuerySet
+
+# PolymorphicQuerySet Q objects (and filter()) support these additional key words.
+# These are forbidden as field names (a descriptive exception is raised)
+POLYMORPHIC_SPECIAL_Q_KWORDS = ["instance_of", "not_instance_of"]
+
+DUMPDATA_COMMAND = os.path.join(
+    "django", "core", "management", "commands", "dumpdata.py"
+)
+
+
+class ManagerInheritanceWarning(RuntimeWarning):
+    pass
+
+
+###################################################################################
+# PolymorphicModel meta class
+
+
+class PolymorphicModelBase(ModelBase):
+    """
+    Manager inheritance is a pretty complex topic which may need
+    more thought regarding how this should be handled for polymorphic
+    models.
+
+    In any case, we probably should propagate 'objects' and 'base_objects'
+    from PolymorphicModel to every subclass. We also want to somehow
+    inherit/propagate _default_manager as well, as it needs to be polymorphic.
+
+    The current implementation below is an experiment to solve this
+    problem with a very simplistic approach: We unconditionally
+    inherit/propagate any and all managers (using _copy_to_model),
+    as long as they are defined on polymorphic models
+    (the others are left alone).
+
+    Like Django ModelBase, we special-case _default_manager:
+    if there are any user-defined managers, it is set to the first of these.
+
+    We also require that _default_manager as well as any user defined
+    polymorphic managers produce querysets that are derived from
+    PolymorphicQuerySet.
+    """
+
+    def __new__(self, model_name, bases, attrs):
+        # print; print '###', model_name, '- bases:', bases
+
+        # Workaround compatibility issue with six.with_metaclass() and custom Django model metaclasses:
+        if not attrs and model_name == "NewBase":
+            return super(PolymorphicModelBase, self).__new__(
+                self, model_name, bases, attrs
+            )
+
+        # Make sure that manager_inheritance_from_future is set, since django-polymorphic 1.x already
+        # simulated that behavior on the polymorphic manager to all subclasses behave like polymorphics
+        if django.VERSION < (2, 0):
+            if "Meta" in attrs:
+                if not hasattr(attrs["Meta"], "manager_inheritance_from_future"):
+                    attrs["Meta"].manager_inheritance_from_future = True
+            else:
+                attrs["Meta"] = type(
+                    "Meta", (object,), {"manager_inheritance_from_future": True}
+                )
+
+        # create new model
+        new_class = self.call_superclass_new_method(model_name, bases, attrs)
+
+        # check if the model fields are all allowed
+        self.validate_model_fields(new_class)
+
+        # validate resulting default manager
+        if not new_class._meta.abstract and not new_class._meta.swapped:
+            self.validate_model_manager(new_class.objects, model_name, "objects")
+
+        # for __init__ function of this class (monkeypatching inheritance accessors)
+        new_class.polymorphic_super_sub_accessors_replaced = False
+
+        # determine the name of the primary key field and store it into the class variable
+        # polymorphic_primary_key_name (it is needed by query.py)
+        for f in new_class._meta.fields:
+            if f.primary_key and type(f) != models.OneToOneField:
+                new_class.polymorphic_primary_key_name = f.name
+                break
+
+        return new_class
+
+    @classmethod
+    def call_superclass_new_method(self, model_name, bases, attrs):
+        """call __new__ method of super class and return the newly created class.
+        Also work around a limitation in Django's ModelBase."""
+        # There seems to be a general limitation in Django's app_label handling
+        # regarding abstract models (in ModelBase). See issue 1 on github - TODO: propose patch for Django
+        # We run into this problem if polymorphic.py is located in a top-level directory
+        # which is directly in the python path. To work around this we temporarily set
+        # app_label here for PolymorphicModel.
+        meta = attrs.get("Meta", None)
+        do_app_label_workaround = (
+            meta
+            and attrs["__module__"] == "polymorphic"
+            and model_name == "PolymorphicModel"
+            and getattr(meta, "app_label", None) is None
+        )
+
+        if do_app_label_workaround:
+            meta.app_label = "poly_dummy_app_label"
+        new_class = super(PolymorphicModelBase, self).__new__(
+            self, model_name, bases, attrs
+        )
+        if do_app_label_workaround:
+            del meta.app_label
+        return new_class
+
+    @classmethod
+    def validate_model_fields(self, new_class):
+        "check if all fields names are allowed (i.e. not in POLYMORPHIC_SPECIAL_Q_KWORDS)"
+        for f in new_class._meta.fields:
+            if f.name in POLYMORPHIC_SPECIAL_Q_KWORDS:
+                e = 'PolymorphicModel: "%s" - field name "%s" is not allowed in polymorphic models'
+                raise AssertionError(e % (new_class.__name__, f.name))
+
+    @classmethod
+    def validate_model_manager(self, manager, model_name, manager_name):
+        """check if the manager is derived from PolymorphicManager
+        and its querysets from PolymorphicQuerySet - throw AssertionError if not"""
+
+        if not issubclass(type(manager), PolymorphicManager):
+            if django.VERSION < (2, 0):
+                extra = "\nConsider using Meta.manager_inheritance_from_future = True for Django 1.x projects"
+            else:
+                extra = ""
+            e = (
+                'PolymorphicModel: "{0}.{1}" manager is of type "{2}", but must be a subclass of'
+                " PolymorphicManager.{extra} to support retrieving subclasses".format(
+                    model_name, manager_name, type(manager).__name__, extra=extra
+                )
+            )
+            warnings.warn(e, ManagerInheritanceWarning, stacklevel=3)
+            return manager
+
+        if not getattr(manager, "queryset_class", None) or not issubclass(
+            manager.queryset_class, PolymorphicQuerySet
+        ):
+            e = (
+                'PolymorphicModel: "{0}.{1}" has been instantiated with a queryset class '
+                "which is not a subclass of PolymorphicQuerySet (which is required)".format(
+                    model_name, manager_name
+                )
+            )
+            warnings.warn(e, ManagerInheritanceWarning, stacklevel=3)
+        return manager
+
+    @property
+    def base_objects(self):
+        warnings.warn(
+            "Using PolymorphicModel.base_objects is deprecated.\n"
+            "Use {0}.objects.non_polymorphic() instead.".format(
+                self.__class__.__name__
+            ),
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        return self._base_objects
+
+    @property
+    def _base_objects(self):
+        # Create a manager so the API works as expected. Just don't register it
+        # anymore in the Model Meta, so it doesn't substitute our polymorphic
+        # manager as default manager for the third level of inheritance when
+        # that third level doesn't define a manager at all.
+        manager = models.Manager()
+        manager.name = "base_objects"
+        manager.model = self
+        return manager
+
+    @property
+    def _default_manager(self):
+        if len(sys.argv) > 1 and sys.argv[1] == "dumpdata":
+            # TODO: investigate Django how this can be avoided
+            # hack: a small patch to Django would be a better solution.
+            # Django's management command 'dumpdata' relies on non-polymorphic
+            # behaviour of the _default_manager. Therefore, we catch any access to _default_manager
+            # here and return the non-polymorphic default manager instead if we are called from 'dumpdata.py'
+            # Otherwise, the base objects will be upcasted to polymorphic models, and be outputted as such.
+            # (non-polymorphic default manager is 'base_objects' for polymorphic models).
+            # This way we don't need to patch django.core.management.commands.dumpdata
+            # for all supported Django versions.
+            frm = inspect.stack()[
+                1
+            ]  # frm[1] is caller file name, frm[3] is caller function name
+            if DUMPDATA_COMMAND in frm[1]:
+                return self._base_objects
+
+        manager = super(PolymorphicModelBase, self)._default_manager
+        if not isinstance(manager, PolymorphicManager):
+            warnings.warn(
+                "{0}._default_manager is not a PolymorphicManager".format(
+                    self.__class__.__name__
+                ),
+                ManagerInheritanceWarning,
+            )
+
+        return manager

venv/lib/python3.8/site-packages/polymorphic/compat.py

@@ -0,0 +1,45 @@
+"""Compatibility with Python 2 (taken from 'django.utils.six')"""
+import sys
+
+PY2 = sys.version_info[0] == 2
+PY3 = sys.version_info[0] == 3
+
+
+if PY3:
+    string_types = (str,)
+    integer_types = (int,)
+    class_types = (type,)
+    text_type = str
+    binary_type = bytes
+
+    MAXSIZE = sys.maxsize
+else:
+    string_types = (basestring,)
+    integer_types = (int, long)
+
+
+def with_metaclass(meta, *bases):
+    class metaclass(type):
+        def __new__(cls, name, this_bases, d):
+            return meta(name, bases, d)
+
+    return type.__new__(metaclass, "temporary_class", (), {})
+
+
+def python_2_unicode_compatible(klass):
+    """
+    A decorator that defines __unicode__ and __str__ methods under Python 2.
+    Under Python 3 it does nothing.
+
+    To support Python 2 and 3 with a single code base, define a __str__ method
+    returning text and apply this decorator to the class.
+    """
+    if PY2:
+        if "__str__" not in klass.__dict__:
+            raise ValueError(
+                "@python_2_unicode_compatible cannot be applied "
+                "to %s because it doesn't define __str__()." % klass.__name__
+            )
+        klass.__unicode__ = klass.__str__
+        klass.__str__ = lambda self: self.__unicode__().encode("utf-8")
+    return klass

venv/lib/python3.8/site-packages/polymorphic/contrib/extra_views.py

@@ -0,0 +1,142 @@
+"""
+The ``extra_views.formsets`` provides a simple way to handle formsets.
+The ``extra_views.advanced`` provides a method to combine that with a create/update form.
+
+This package provides classes that support both options for polymorphic formsets.
+"""
+from __future__ import absolute_import
+
+import extra_views
+from django.core.exceptions import ImproperlyConfigured
+
+from polymorphic.formsets import (
+    BasePolymorphicInlineFormSet,
+    BasePolymorphicModelFormSet,
+    polymorphic_child_forms_factory,
+)
+
+__all__ = (
+    "PolymorphicFormSetView",
+    "PolymorphicInlineFormSetView",
+    "PolymorphicInlineFormSet",
+)
+
+
+class PolymorphicFormSetMixin(object):
+    """
+    Internal Mixin, that provides polymorphic integration with the ``extra_views`` package.
+    """
+
+    formset_class = BasePolymorphicModelFormSet
+
+    #: Default 0 extra forms
+    factory_kwargs = {"extra": 0}
+
+    #: Define the children
+    # :type: list[PolymorphicFormSetChild]
+    formset_children = None
+
+    def get_formset_children(self):
+        """
+        :rtype: list[PolymorphicFormSetChild]
+        """
+        if not self.formset_children:
+            raise ImproperlyConfigured(
+                "Define 'formset_children' as list of `PolymorphicFormSetChild`"
+            )
+        return self.formset_children
+
+    def get_formset_child_kwargs(self):
+        return {}
+
+    def get_formset(self):
+        """
+        Returns the formset class from the inline formset factory
+        """
+        # Implementation detail:
+        # Since `polymorphic_modelformset_factory` and `polymorphic_inlineformset_factory` mainly
+        # reuse the standard factories, and then add `child_forms`, the same can be done here.
+        # This makes sure the base class construction is completely honored.
+        FormSet = super(PolymorphicFormSetMixin, self).get_formset()
+        FormSet.child_forms = polymorphic_child_forms_factory(
+            self.get_formset_children(), **self.get_formset_child_kwargs()
+        )
+        return FormSet
+
+
+class PolymorphicFormSetView(PolymorphicFormSetMixin, extra_views.ModelFormSetView):
+    """
+    A view that displays a single polymorphic formset.
+
+    .. code-block:: python
+
+        from polymorphic.formsets import PolymorphicFormSetChild
+
+
+        class ItemsView(PolymorphicFormSetView):
+            model = Item
+            formset_children = [
+                PolymorphicFormSetChild(ItemSubclass1),
+                PolymorphicFormSetChild(ItemSubclass2),
+            ]
+
+    """
+
+    formset_class = BasePolymorphicModelFormSet
+
+
+class PolymorphicInlineFormSetView(
+    PolymorphicFormSetMixin, extra_views.InlineFormSetView
+):
+    """
+    A view that displays a single polymorphic formset - with one parent object.
+    This is a variation of the :mod:`extra_views` package classes for django-polymorphic.
+
+    .. code-block:: python
+
+        from polymorphic.formsets import PolymorphicFormSetChild
+
+
+        class OrderItemsView(PolymorphicInlineFormSetView):
+            model = Order
+            inline_model = Item
+            formset_children = [
+                PolymorphicFormSetChild(ItemSubclass1),
+                PolymorphicFormSetChild(ItemSubclass2),
+            ]
+    """
+
+    formset_class = BasePolymorphicInlineFormSet
+
+
+class PolymorphicInlineFormSet(
+    PolymorphicFormSetMixin, extra_views.InlineFormSetFactory
+):
+    """
+    An inline to add to the ``inlines`` of
+    the :class:`~extra_views.advanced.CreateWithInlinesView`
+    and :class:`~extra_views.advanced.UpdateWithInlinesView` class.
+
+    .. code-block:: python
+
+        from polymorphic.formsets import PolymorphicFormSetChild
+
+
+        class ItemsInline(PolymorphicInlineFormSet):
+            model = Item
+            formset_children = [
+                PolymorphicFormSetChild(ItemSubclass1),
+                PolymorphicFormSetChild(ItemSubclass2),
+            ]
+
+
+        class OrderCreateView(CreateWithInlinesView):
+            model = Order
+            inlines = [ItemsInline]
+
+            def get_success_url(self):
+                return self.object.get_absolute_url()
+
+    """
+
+    formset_class = BasePolymorphicInlineFormSet

venv/lib/python3.8/site-packages/polymorphic/contrib/guardian.py

@@ -0,0 +1,35 @@
+from django.contrib.contenttypes.models import ContentType
+
+
+def get_polymorphic_base_content_type(obj):
+    """
+    Helper function to return the base polymorphic content type id. This should used with django-guardian and the
+    GUARDIAN_GET_CONTENT_TYPE option.
+
+    See the django-guardian documentation for more information:
+
+    https://django-guardian.readthedocs.io/en/latest/configuration.html#guardian-get-content-type
+    """
+    if hasattr(obj, "polymorphic_model_marker"):
+        try:
+            superclasses = list(obj.__class__.mro())
+        except TypeError:
+            # obj is an object so mro() need to be called with the obj.
+            superclasses = list(obj.__class__.mro(obj))
+
+        polymorphic_superclasses = list()
+        for sclass in superclasses:
+            if hasattr(sclass, "polymorphic_model_marker"):
+                polymorphic_superclasses.append(sclass)
+
+        # PolymorphicMPTT adds an additional class between polymorphic and base class.
+        if hasattr(obj, "can_have_children"):
+            root_polymorphic_class = polymorphic_superclasses[-3]
+        else:
+            root_polymorphic_class = polymorphic_superclasses[-2]
+        ctype = ContentType.objects.get_for_model(root_polymorphic_class)
+
+    else:
+        ctype = ContentType.objects.get_for_model(obj)
+
+    return ctype

venv/lib/python3.8/site-packages/polymorphic/formsets/__init__.py

@@ -0,0 +1,37 @@
+"""
+This allows creating formsets where each row can be a different form type.
+The logic of the formsets work similar to the standard Django formsets;
+there are factory methods to construct the classes with the proper form settings.
+
+The "parent" formset hosts the entire model and their child model.
+For every child type, there is an :class:`PolymorphicFormSetChild` instance
+that describes how to display and construct the child.
+It's parameters are very similar to the parent's factory method.
+"""
+from .generic import (  # Can import generic here, as polymorphic already depends on the 'contenttypes' app.
+    BaseGenericPolymorphicInlineFormSet,
+    GenericPolymorphicFormSetChild,
+    generic_polymorphic_inlineformset_factory,
+)
+from .models import (
+    BasePolymorphicInlineFormSet,
+    BasePolymorphicModelFormSet,
+    PolymorphicFormSetChild,
+    UnsupportedChildType,
+    polymorphic_child_forms_factory,
+    polymorphic_inlineformset_factory,
+    polymorphic_modelformset_factory,
+)
+
+__all__ = (
+    "BasePolymorphicModelFormSet",
+    "BasePolymorphicInlineFormSet",
+    "PolymorphicFormSetChild",
+    "UnsupportedChildType",
+    "polymorphic_modelformset_factory",
+    "polymorphic_inlineformset_factory",
+    "polymorphic_child_forms_factory",
+    "BaseGenericPolymorphicInlineFormSet",
+    "GenericPolymorphicFormSetChild",
+    "generic_polymorphic_inlineformset_factory",
+)

venv/lib/python3.8/site-packages/polymorphic/formsets/generic.py

@@ -0,0 +1,136 @@
+from django.contrib.contenttypes.forms import (
+    BaseGenericInlineFormSet,
+    generic_inlineformset_factory,
+)
+from django.contrib.contenttypes.models import ContentType
+from django.db import models
+from django.forms.models import ModelForm
+
+from .models import (
+    BasePolymorphicModelFormSet,
+    PolymorphicFormSetChild,
+    polymorphic_child_forms_factory,
+)
+
+
+class GenericPolymorphicFormSetChild(PolymorphicFormSetChild):
+    """
+    Formset child for generic inlines
+    """
+
+    def __init__(self, *args, **kwargs):
+        self.ct_field = kwargs.pop("ct_field", "content_type")
+        self.fk_field = kwargs.pop("fk_field", "object_id")
+        super(GenericPolymorphicFormSetChild, self).__init__(*args, **kwargs)
+
+    def get_form(self, ct_field="content_type", fk_field="object_id", **kwargs):
+        """
+        Construct the form class for the formset child.
+        """
+        exclude = list(self.exclude)
+        extra_exclude = kwargs.pop("extra_exclude", None)
+        if extra_exclude:
+            exclude += list(extra_exclude)
+
+        # Make sure the GFK fields are excluded by default
+        # This is similar to what generic_inlineformset_factory() does
+        # if there is no field called `ct_field` let the exception propagate
+        opts = self.model._meta
+        ct_field = opts.get_field(self.ct_field)
+
+        if (
+            not isinstance(ct_field, models.ForeignKey)
+            or ct_field.remote_field.model != ContentType
+        ):
+            raise Exception(
+                "fk_name '%s' is not a ForeignKey to ContentType" % ct_field
+            )
+
+        fk_field = opts.get_field(self.fk_field)  # let the exception propagate
+        exclude.extend([ct_field.name, fk_field.name])
+        kwargs["exclude"] = exclude
+
+        return super(GenericPolymorphicFormSetChild, self).get_form(**kwargs)
+
+
+class BaseGenericPolymorphicInlineFormSet(
+    BaseGenericInlineFormSet, BasePolymorphicModelFormSet
+):
+    """
+    Polymorphic formset variation for inline generic formsets
+    """
+
+
+def generic_polymorphic_inlineformset_factory(
+    model,
+    formset_children,
+    form=ModelForm,
+    formset=BaseGenericPolymorphicInlineFormSet,
+    ct_field="content_type",
+    fk_field="object_id",
+    # Base form
+    # TODO: should these fields be removed in favor of creating
+    # the base form as a formset child too?
+    fields=None,
+    exclude=None,
+    extra=1,
+    can_order=False,
+    can_delete=True,
+    max_num=None,
+    formfield_callback=None,
+    validate_max=False,
+    for_concrete_model=True,
+    min_num=None,
+    validate_min=False,
+    child_form_kwargs=None,
+):
+    """
+    Construct the class for a generic inline polymorphic formset.
+
+    All arguments are identical to :func:`~django.contrib.contenttypes.forms.generic_inlineformset_factory`,
+    with the exception of the ``formset_children`` argument.
+
+    :param formset_children: A list of all child :class:`PolymorphicFormSetChild` objects
+                             that tell the inline how to render the child model types.
+    :type formset_children: Iterable[PolymorphicFormSetChild]
+    :rtype: type
+    """
+    kwargs = {
+        "model": model,
+        "form": form,
+        "formfield_callback": formfield_callback,
+        "formset": formset,
+        "ct_field": ct_field,
+        "fk_field": fk_field,
+        "extra": extra,
+        "can_delete": can_delete,
+        "can_order": can_order,
+        "fields": fields,
+        "exclude": exclude,
+        "min_num": min_num,
+        "max_num": max_num,
+        "validate_min": validate_min,
+        "validate_max": validate_max,
+        "for_concrete_model": for_concrete_model,
+        # 'localized_fields': localized_fields,
+        # 'labels': labels,
+        # 'help_texts': help_texts,
+        # 'error_messages': error_messages,
+        # 'field_classes': field_classes,
+    }
+    if child_form_kwargs is None:
+        child_form_kwargs = {}
+
+    child_kwargs = {
+        # 'exclude': exclude,
+        "ct_field": ct_field,
+        "fk_field": fk_field,
+    }
+    if child_form_kwargs:
+        child_kwargs.update(child_form_kwargs)
+
+    FormSet = generic_inlineformset_factory(**kwargs)
+    FormSet.child_forms = polymorphic_child_forms_factory(
+        formset_children, **child_kwargs
+    )
+    return FormSet

venv/lib/python3.8/site-packages/polymorphic/formsets/models.py

@@ -0,0 +1,456 @@
+from collections import OrderedDict
+
+from django import forms
+from django.contrib.contenttypes.models import ContentType
+from django.core.exceptions import ImproperlyConfigured, ValidationError
+from django.forms.models import (
+    BaseInlineFormSet,
+    BaseModelFormSet,
+    ModelForm,
+    inlineformset_factory,
+    modelform_factory,
+    modelformset_factory,
+)
+from django.utils.functional import cached_property
+
+from polymorphic.models import PolymorphicModel
+
+from .utils import add_media
+
+
+class UnsupportedChildType(LookupError):
+    pass
+
+
+class PolymorphicFormSetChild(object):
+    """
+    Metadata to define the inline of a polymorphic child.
+    Provide this information in the :func:'polymorphic_inlineformset_factory' construction.
+    """
+
+    def __init__(
+        self,
+        model,
+        form=ModelForm,
+        fields=None,
+        exclude=None,
+        formfield_callback=None,
+        widgets=None,
+        localized_fields=None,
+        labels=None,
+        help_texts=None,
+        error_messages=None,
+    ):
+
+        self.model = model
+
+        # Instead of initializing the form here right away,
+        # the settings are saved so get_form() can receive additional exclude kwargs.
+        # This is mostly needed for the generic inline formsets
+        self._form_base = form
+        self.fields = fields
+        self.exclude = exclude or ()
+        self.formfield_callback = formfield_callback
+        self.widgets = widgets
+        self.localized_fields = localized_fields
+        self.labels = labels
+        self.help_texts = help_texts
+        self.error_messages = error_messages
+
+    @cached_property
+    def content_type(self):
+        """
+        Expose the ContentType that the child relates to.
+        This can be used for the ''polymorphic_ctype'' field.
+        """
+        return ContentType.objects.get_for_model(self.model, for_concrete_model=False)
+
+    def get_form(self, **kwargs):
+        """
+        Construct the form class for the formset child.
+        """
+        # Do what modelformset_factory() / inlineformset_factory() does to the 'form' argument;
+        # Construct the form with the given ModelFormOptions values
+
+        # Fields can be overwritten. To support the global 'polymorphic_child_forms_factory' kwargs,
+        # that doesn't completely replace all 'exclude' settings defined per child type,
+        # we allow to define things like 'extra_...' fields that are amended to the current child settings.
+
+        exclude = list(self.exclude)
+        extra_exclude = kwargs.pop("extra_exclude", None)
+        if extra_exclude:
+            exclude += list(extra_exclude)
+
+        defaults = {
+            "form": self._form_base,
+            "formfield_callback": self.formfield_callback,
+            "fields": self.fields,
+            "exclude": exclude,
+            # 'for_concrete_model': for_concrete_model,
+            "localized_fields": self.localized_fields,
+            "labels": self.labels,
+            "help_texts": self.help_texts,
+            "error_messages": self.error_messages,
+            # 'field_classes': field_classes,
+        }
+        defaults.update(kwargs)
+
+        return modelform_factory(self.model, **defaults)
+
+
+def polymorphic_child_forms_factory(formset_children, **kwargs):
+    """
+    Construct the forms for the formset children.
+    This is mostly used internally, and rarely needs to be used by external projects.
+    When using the factory methods (:func:'polymorphic_inlineformset_factory'),
+    this feature is called already for you.
+    """
+    child_forms = OrderedDict()
+
+    for formset_child in formset_children:
+        child_forms[formset_child.model] = formset_child.get_form(**kwargs)
+
+    return child_forms
+
+
+class BasePolymorphicModelFormSet(BaseModelFormSet):
+    """
+    A formset that can produce different forms depending on the object type.
+
+    Note that the 'add' feature is therefore more complex,
+    as all variations need ot be exposed somewhere.
+
+    When switching existing formsets to the polymorphic formset,
+    note that the ID field will no longer be named ''model_ptr'',
+    but just appear as ''id''.
+    """
+
+    # Assigned by the factory
+    child_forms = OrderedDict()
+
+    def __init__(self, *args, **kwargs):
+        super(BasePolymorphicModelFormSet, self).__init__(*args, **kwargs)
+        self.queryset_data = self.get_queryset()
+
+    def _construct_form(self, i, **kwargs):
+        """
+        Create the form, depending on the model that's behind it.
+        """
+        # BaseModelFormSet logic
+        if self.is_bound and i < self.initial_form_count():
+            pk_key = "%s-%s" % (self.add_prefix(i), self.model._meta.pk.name)
+            pk = self.data[pk_key]
+            pk_field = self.model._meta.pk
+            to_python = self._get_to_python(pk_field)
+            pk = to_python(pk)
+            kwargs["instance"] = self._existing_object(pk)
+        if i < self.initial_form_count() and "instance" not in kwargs:
+            kwargs["instance"] = self.get_queryset()[i]
+        if i >= self.initial_form_count() and self.initial_extra:
+            # Set initial values for extra forms
+            try:
+                kwargs["initial"] = self.initial_extra[i - self.initial_form_count()]
+            except IndexError:
+                pass
+
+        # BaseFormSet logic, with custom formset_class
+        defaults = {
+            "auto_id": self.auto_id,
+            "prefix": self.add_prefix(i),
+            "error_class": self.error_class,
+        }
+        if self.is_bound:
+            defaults["data"] = self.data
+            defaults["files"] = self.files
+        if self.initial and "initial" not in kwargs:
+            try:
+                defaults["initial"] = self.initial[i]
+            except IndexError:
+                pass
+        # Allow extra forms to be empty, unless they're part of
+        # the minimum forms.
+        if i >= self.initial_form_count() and i >= self.min_num:
+            defaults["empty_permitted"] = True
+            defaults["use_required_attribute"] = False
+        defaults.update(kwargs)
+
+        # Need to find the model that will be displayed in this form.
+        # Hence, peeking in the self.queryset_data beforehand.
+        if self.is_bound:
+            if "instance" in defaults:
+                # Object is already bound to a model, won't change the content type
+                model = defaults[
+                    "instance"
+                ].get_real_instance_class()  # allow proxy models
+            else:
+                # Extra or empty form, use the provided type.
+                # Note this completely tru
+                prefix = defaults["prefix"]
+                try:
+                    ct_id = int(self.data["{0}-polymorphic_ctype".format(prefix)])
+                except (KeyError, ValueError):
+                    raise ValidationError(
+                        "Formset row {0} has no 'polymorphic_ctype' defined!".format(
+                            prefix
+                        )
+                    )
+
+                model = ContentType.objects.get_for_id(ct_id).model_class()
+                if model not in self.child_forms:
+                    # Perform basic validation, as we skip the ChoiceField here.
+                    raise UnsupportedChildType(
+                        "Child model type {0} is not part of the formset".format(model)
+                    )
+        else:
+            if "instance" in defaults:
+                model = defaults[
+                    "instance"
+                ].get_real_instance_class()  # allow proxy models
+            elif "polymorphic_ctype" in defaults.get("initial", {}):
+                model = defaults["initial"]["polymorphic_ctype"].model_class()
+            elif i < len(self.queryset_data):
+                model = self.queryset_data[i].__class__
+            else:
+                # Extra forms, cycle between all types
+                # TODO: take the 'extra' value of each child formset into account.
+                total_known = len(self.queryset_data)
+                child_models = list(self.child_forms.keys())
+                model = child_models[(i - total_known) % len(child_models)]
+
+        form_class = self.get_form_class(model)
+        form = form_class(**defaults)
+        self.add_fields(form, i)
+        return form
+
+    def add_fields(self, form, index):
+        """Add a hidden field for the content type."""
+        ct = ContentType.objects.get_for_model(
+            form._meta.model, for_concrete_model=False
+        )
+        choices = [(ct.pk, ct)]  # Single choice, existing forms can't change the value.
+        form.fields["polymorphic_ctype"] = forms.ChoiceField(
+            choices=choices, initial=ct.pk, required=False, widget=forms.HiddenInput
+        )
+        super(BasePolymorphicModelFormSet, self).add_fields(form, index)
+
+    def get_form_class(self, model):
+        """
+        Return the proper form class for the given model.
+        """
+        if not self.child_forms:
+            raise ImproperlyConfigured(
+                "No 'child_forms' defined in {0}".format(self.__class__.__name__)
+            )
+        if not issubclass(model, PolymorphicModel):
+            raise TypeError("Expect polymorphic model type, not {0}".format(model))
+
+        try:
+            return self.child_forms[model]
+        except KeyError:
+            # This may happen when the query returns objects of a type that was not handled by the formset.
+            raise UnsupportedChildType(
+                "The '{0}' found a '{1}' model in the queryset, "
+                "but no form class is registered to display it.".format(
+                    self.__class__.__name__, model.__name__
+                )
+            )
+
+    def is_multipart(self):
+        """
+        Returns True if the formset needs to be multipart, i.e. it
+        has FileInput. Otherwise, False.
+        """
+        return any(f.is_multipart() for f in self.empty_forms)
+
+    @property
+    def media(self):
+        # Include the media of all form types.
+        # The form media includes all form widget media
+        media = forms.Media()
+        for form in self.empty_forms:
+            add_media(media, form.media)
+        return media
+
+    @cached_property
+    def empty_forms(self):
+        """
+        Return all possible empty forms
+        """
+        forms = []
+        for model, form_class in self.child_forms.items():
+            kwargs = self.get_form_kwargs(None)
+
+            form = form_class(
+                auto_id=self.auto_id,
+                prefix=self.add_prefix("__prefix__"),
+                empty_permitted=True,
+                use_required_attribute=False,
+                **kwargs
+            )
+            self.add_fields(form, None)
+            forms.append(form)
+        return forms
+
+    @property
+    def empty_form(self):
+        # TODO: make an exception when can_add_base is defined?
+        raise RuntimeError(
+            "'empty_form' is not used in polymorphic formsets, use 'empty_forms' instead."
+        )
+
+
+def polymorphic_modelformset_factory(
+    model,
+    formset_children,
+    formset=BasePolymorphicModelFormSet,
+    # Base field
+    # TODO: should these fields be removed in favor of creating
+    # the base form as a formset child too?
+    form=ModelForm,
+    fields=None,
+    exclude=None,
+    extra=1,
+    can_order=False,
+    can_delete=True,
+    max_num=None,
+    formfield_callback=None,
+    widgets=None,
+    validate_max=False,
+    localized_fields=None,
+    labels=None,
+    help_texts=None,
+    error_messages=None,
+    min_num=None,
+    validate_min=False,
+    field_classes=None,
+    child_form_kwargs=None,
+):
+    """
+    Construct the class for an polymorphic model formset.
+
+    All arguments are identical to :func:'~django.forms.models.modelformset_factory',
+    with the exception of the ''formset_children'' argument.
+
+    :param formset_children: A list of all child :class:'PolymorphicFormSetChild' objects
+                             that tell the inline how to render the child model types.
+    :type formset_children: Iterable[PolymorphicFormSetChild]
+    :rtype: type
+    """
+    kwargs = {
+        "model": model,
+        "form": form,
+        "formfield_callback": formfield_callback,
+        "formset": formset,
+        "extra": extra,
+        "can_delete": can_delete,
+        "can_order": can_order,
+        "fields": fields,
+        "exclude": exclude,
+        "min_num": min_num,
+        "max_num": max_num,
+        "widgets": widgets,
+        "validate_min": validate_min,
+        "validate_max": validate_max,
+        "localized_fields": localized_fields,
+        "labels": labels,
+        "help_texts": help_texts,
+        "error_messages": error_messages,
+        "field_classes": field_classes,
+    }
+    FormSet = modelformset_factory(**kwargs)
+
+    child_kwargs = {
+        # 'exclude': exclude,
+    }
+    if child_form_kwargs:
+        child_kwargs.update(child_form_kwargs)
+
+    FormSet.child_forms = polymorphic_child_forms_factory(
+        formset_children, **child_kwargs
+    )
+    return FormSet
+
+
+class BasePolymorphicInlineFormSet(BaseInlineFormSet, BasePolymorphicModelFormSet):
+    """
+    Polymorphic formset variation for inline formsets
+    """
+
+    def _construct_form(self, i, **kwargs):
+        return super(BasePolymorphicInlineFormSet, self)._construct_form(i, **kwargs)
+
+
+def polymorphic_inlineformset_factory(
+    parent_model,
+    model,
+    formset_children,
+    formset=BasePolymorphicInlineFormSet,
+    fk_name=None,
+    # Base field
+    # TODO: should these fields be removed in favor of creating
+    # the base form as a formset child too?
+    form=ModelForm,
+    fields=None,
+    exclude=None,
+    extra=1,
+    can_order=False,
+    can_delete=True,
+    max_num=None,
+    formfield_callback=None,
+    widgets=None,
+    validate_max=False,
+    localized_fields=None,
+    labels=None,
+    help_texts=None,
+    error_messages=None,
+    min_num=None,
+    validate_min=False,
+    field_classes=None,
+    child_form_kwargs=None,
+):
+    """
+    Construct the class for an inline polymorphic formset.
+
+    All arguments are identical to :func:'~django.forms.models.inlineformset_factory',
+    with the exception of the ''formset_children'' argument.
+
+    :param formset_children: A list of all child :class:'PolymorphicFormSetChild' objects
+                             that tell the inline how to render the child model types.
+    :type formset_children: Iterable[PolymorphicFormSetChild]
+    :rtype: type
+    """
+    kwargs = {
+        "parent_model": parent_model,
+        "model": model,
+        "form": form,
+        "formfield_callback": formfield_callback,
+        "formset": formset,
+        "fk_name": fk_name,
+        "extra": extra,
+        "can_delete": can_delete,
+        "can_order": can_order,
+        "fields": fields,
+        "exclude": exclude,
+        "min_num": min_num,
+        "max_num": max_num,
+        "widgets": widgets,
+        "validate_min": validate_min,
+        "validate_max": validate_max,
+        "localized_fields": localized_fields,
+        "labels": labels,
+        "help_texts": help_texts,
+        "error_messages": error_messages,
+        "field_classes": field_classes,
+    }
+    FormSet = inlineformset_factory(**kwargs)
+
+    child_kwargs = {
+        # 'exclude': exclude,
+    }
+    if child_form_kwargs:
+        child_kwargs.update(child_form_kwargs)
+
+    FormSet.child_forms = polymorphic_child_forms_factory(
+        formset_children, **child_kwargs
+    )
+    return FormSet

venv/lib/python3.8/site-packages/polymorphic/formsets/utils.py

@@ -0,0 +1,20 @@
+"""
+Internal utils
+"""
+import django
+
+
+def add_media(dest, media):
+    """
+    Optimized version of django.forms.Media.__add__() that doesn't create new objects.
+    """
+    if django.VERSION >= (2, 2):
+        dest._css_lists.extend(media._css_lists)
+        dest._js_lists.extend(media._js_lists)
+    elif django.VERSION >= (2, 0):
+        combined = dest + media
+        dest._css = combined._css
+        dest._js = combined._js
+    else:
+        dest.add_css(media._css)
+        dest.add_js(media._js)

venv/lib/python3.8/site-packages/polymorphic/locale/en/LC_MESSAGES/django.po

@@ -0,0 +1,31 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the PACKAGE package.
+# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PACKAGE VERSION\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2013-11-29 18:12+0100\n"
+"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+"Language-Team: LANGUAGE <LL@li.org>\n"
+"Language: \n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+
+#: admin.py:41
+msgid "Type"
+msgstr ""
+
+#: admin.py:56
+msgid "Content type"
+msgstr ""
+
+
+#: admin.py:403
+msgid "Contents"
+msgstr ""

venv/lib/python3.8/site-packages/polymorphic/locale/es/LC_MESSAGES/django.po

@@ -0,0 +1,31 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the PACKAGE package.
+# Gonzalo Bustos, 2015.
+#
+msgid ""
+msgstr ""
+"Project-Id-Version: \n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2013-11-29 18:12+0100\n"
+"PO-Revision-Date: 2015-10-12 11:42-0300\n"
+"Last-Translator: Gonzalo Bustos\n"
+"Language-Team: Spanish <LL@li.org>\n"
+"Language: es\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"X-Generator: Poedit 1.6.10\n"
+
+#: admin.py:41
+msgid "Type"
+msgstr "Tipo"
+
+#: admin.py:56
+msgid "Content type"
+msgstr "Tipo de contenido"
+
+#: admin.py:333 admin.py:403
+#, python-format
+msgid "Contents"
+msgstr "Contenidos"

venv/lib/python3.8/site-packages/polymorphic/locale/fr/LC_MESSAGES/django.po

@@ -0,0 +1,37 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the PACKAGE package.
+# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PACKAGE VERSION\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2013-11-29 18:12+0100\n"
+"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+"Language-Team: LANGUAGE <LL@li.org>\n"
+"Language: \n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=2; plural=(n > 1);\n"
+
+#: admin.py:41
+msgid "Type"
+msgstr "Type"
+
+#: admin.py:56
+msgid "Content type"
+msgstr "Type de contenu"
+
+# This is already translated in Django
+# #: admin.py:333
+# #, python-format
+# msgid "Add %s"
+# msgstr ""
+
+#: admin.py:403
+msgid "Contents"
+msgstr "Contenus"

venv/lib/python3.8/site-packages/polymorphic/managers.py

@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+"""
+The manager class for use in the models.
+"""
+from __future__ import unicode_literals
+
+from django.db import models
+
+from polymorphic.compat import python_2_unicode_compatible
+from polymorphic.query import PolymorphicQuerySet
+
+__all__ = ("PolymorphicManager", "PolymorphicQuerySet")
+
+
+@python_2_unicode_compatible
+class PolymorphicManager(models.Manager):
+    """
+    Manager for PolymorphicModel
+
+    Usually not explicitly needed, except if a custom manager or
+    a custom queryset class is to be used.
+    """
+
+    queryset_class = PolymorphicQuerySet
+
+    @classmethod
+    def from_queryset(cls, queryset_class, class_name=None):
+        manager = super(PolymorphicManager, cls).from_queryset(
+            queryset_class, class_name=class_name
+        )
+        # also set our version, Django uses _queryset_class
+        manager.queryset_class = queryset_class
+        return manager
+
+    def get_queryset(self):
+        qs = self.queryset_class(self.model, using=self._db, hints=self._hints)
+        if self.model._meta.proxy:
+            qs = qs.instance_of(self.model)
+        return qs
+
+    def __str__(self):
+        return "%s (PolymorphicManager) using %s" % (
+            self.__class__.__name__,
+            self.queryset_class.__name__,
+        )
+
+    # Proxied methods
+    def non_polymorphic(self):
+        return self.all().non_polymorphic()
+
+    def instance_of(self, *args):
+        return self.all().instance_of(*args)
+
+    def not_instance_of(self, *args):
+        return self.all().not_instance_of(*args)
+
+    def get_real_instances(self, base_result_objects=None):
+        return self.all().get_real_instances(base_result_objects=base_result_objects)

venv/lib/python3.8/site-packages/polymorphic/models.py

@@ -0,0 +1,280 @@
+# -*- coding: utf-8 -*-
+"""
+Seamless Polymorphic Inheritance for Django Models
+"""
+from __future__ import absolute_import
+
+from django.contrib.contenttypes.models import ContentType
+from django.db import models
+from django.db.models.fields.related import (
+    ForwardManyToOneDescriptor,
+    ReverseOneToOneDescriptor,
+)
+from django.db.utils import DEFAULT_DB_ALIAS
+
+from polymorphic.compat import with_metaclass
+
+from .base import PolymorphicModelBase
+from .managers import PolymorphicManager
+from .query_translate import translate_polymorphic_Q_object
+
+###################################################################################
+# PolymorphicModel
+
+
+class PolymorphicTypeUndefined(LookupError):
+    pass
+
+
+class PolymorphicTypeInvalid(RuntimeError):
+    pass
+
+
+class PolymorphicModel(with_metaclass(PolymorphicModelBase, models.Model)):
+    """
+    Abstract base class that provides polymorphic behaviour
+    for any model directly or indirectly derived from it.
+
+    PolymorphicModel declares one field for internal use (:attr:`polymorphic_ctype`)
+    and provides a polymorphic manager as the default manager (and as 'objects').
+    """
+
+    # for PolymorphicModelBase, so it can tell which models are polymorphic and which are not (duck typing)
+    polymorphic_model_marker = True
+
+    # for PolymorphicQuery, True => an overloaded __repr__ with nicer multi-line output is used by PolymorphicQuery
+    polymorphic_query_multiline_output = False
+
+    # avoid ContentType related field accessor clash (an error emitted by model validation)
+    #: The model field that stores the :class:`~django.contrib.contenttypes.models.ContentType` reference to the actual class.
+    polymorphic_ctype = models.ForeignKey(
+        ContentType,
+        null=True,
+        editable=False,
+        on_delete=models.CASCADE,
+        related_name="polymorphic_%(app_label)s.%(class)s_set+",
+    )
+
+    # some applications want to know the name of the fields that are added to its models
+    polymorphic_internal_model_fields = ["polymorphic_ctype"]
+
+    # Note that Django 1.5 removes these managers because the model is abstract.
+    # They are pretended to be there by the metaclass in PolymorphicModelBase.get_inherited_managers()
+    objects = PolymorphicManager()
+
+    class Meta:
+        abstract = True
+        base_manager_name = "objects"
+
+    @classmethod
+    def translate_polymorphic_Q_object(cls, q):
+        return translate_polymorphic_Q_object(cls, q)
+
+    def pre_save_polymorphic(self, using=DEFAULT_DB_ALIAS):
+        """
+        Make sure the ``polymorphic_ctype`` value is correctly set on this model.
+        """
+        # This function may be called manually in special use-cases. When the object
+        # is saved for the first time, we store its real class in polymorphic_ctype.
+        # When the object later is retrieved by PolymorphicQuerySet, it uses this
+        # field to figure out the real class of this object
+        # (used by PolymorphicQuerySet._get_real_instances)
+        if not self.polymorphic_ctype_id:
+            self.polymorphic_ctype = ContentType.objects.db_manager(
+                using
+            ).get_for_model(self, for_concrete_model=False)
+
+    pre_save_polymorphic.alters_data = True
+
+    def save(self, *args, **kwargs):
+        """Calls :meth:`pre_save_polymorphic` and saves the model."""
+        using = kwargs.get("using", self._state.db or DEFAULT_DB_ALIAS)
+        self.pre_save_polymorphic(using=using)
+        return super(PolymorphicModel, self).save(*args, **kwargs)
+
+    save.alters_data = True
+
+    def get_real_instance_class(self):
+        """
+        Return the actual model type of the object.
+
+        If a non-polymorphic manager (like base_objects) has been used to
+        retrieve objects, then the real class/type of these objects may be
+        determined using this method.
+        """
+        if self.polymorphic_ctype_id is None:
+            raise PolymorphicTypeUndefined(
+                (
+                    "The model {}#{} does not have a `polymorphic_ctype_id` value defined.\n"
+                    "If you created models outside polymorphic, e.g. through an import or migration, "
+                    "make sure the `polymorphic_ctype_id` field points to the ContentType ID of the model subclass."
+                ).format(self.__class__.__name__, self.pk)
+            )
+
+        # the following line would be the easiest way to do this, but it produces sql queries
+        # return self.polymorphic_ctype.model_class()
+        # so we use the following version, which uses the ContentType manager cache.
+        # Note that model_class() can return None for stale content types;
+        # when the content type record still exists but no longer refers to an existing model.
+        model = (
+            ContentType.objects.db_manager(self._state.db)
+            .get_for_id(self.polymorphic_ctype_id)
+            .model_class()
+        )
+
+        # Protect against bad imports (dumpdata without --natural) or other
+        # issues missing with the ContentType models.
+        if (
+            model is not None
+            and not issubclass(model, self.__class__)
+            and (
+                self.__class__._meta.proxy_for_model is None
+                or not issubclass(model, self.__class__._meta.proxy_for_model)
+            )
+        ):
+            raise PolymorphicTypeInvalid(
+                "ContentType {0} for {1} #{2} does not point to a subclass!".format(
+                    self.polymorphic_ctype_id, model, self.pk
+                )
+            )
+
+        return model
+
+    def get_real_concrete_instance_class_id(self):
+        model_class = self.get_real_instance_class()
+        if model_class is None:
+            return None
+        return (
+            ContentType.objects.db_manager(self._state.db)
+            .get_for_model(model_class, for_concrete_model=True)
+            .pk
+        )
+
+    def get_real_concrete_instance_class(self):
+        model_class = self.get_real_instance_class()
+        if model_class is None:
+            return None
+        return (
+            ContentType.objects.db_manager(self._state.db)
+            .get_for_model(model_class, for_concrete_model=True)
+            .model_class()
+        )
+
+    def get_real_instance(self):
+        """
+        Upcast an object to it's actual type.
+
+        If a non-polymorphic manager (like base_objects) has been used to
+        retrieve objects, then the complete object with it's real class/type
+        and all fields may be retrieved with this method.
+
+        .. note::
+            Each method call executes one db query (if necessary).
+            Use the :meth:`~polymorphic.managers.PolymorphicQuerySet.get_real_instances`
+            to upcast a complete list in a single efficient query.
+        """
+        real_model = self.get_real_instance_class()
+        if real_model == self.__class__:
+            return self
+        return real_model.objects.db_manager(self._state.db).get(pk=self.pk)
+
+    def __init__(self, *args, **kwargs):
+        """Replace Django's inheritance accessor member functions for our model
+        (self.__class__) with our own versions.
+        We monkey patch them until a patch can be added to Django
+        (which would probably be very small and make all of this obsolete).
+
+        If we have inheritance of the form ModelA -> ModelB ->ModelC then
+        Django creates accessors like this:
+        - ModelA: modelb
+        - ModelB: modela_ptr, modelb, modelc
+        - ModelC: modela_ptr, modelb, modelb_ptr, modelc
+
+        These accessors allow Django (and everyone else) to travel up and down
+        the inheritance tree for the db object at hand.
+
+        The original Django accessors use our polymorphic manager.
+        But they should not. So we replace them with our own accessors that use
+        our appropriate base_objects manager.
+        """
+        super(PolymorphicModel, self).__init__(*args, **kwargs)
+
+        if self.__class__.polymorphic_super_sub_accessors_replaced:
+            return
+        self.__class__.polymorphic_super_sub_accessors_replaced = True
+
+        def create_accessor_function_for_model(model, accessor_name):
+            def accessor_function(self):
+                attr = model._base_objects.get(pk=self.pk)
+                return attr
+
+            return accessor_function
+
+        subclasses_and_superclasses_accessors = (
+            self._get_inheritance_relation_fields_and_models()
+        )
+
+        for name, model in subclasses_and_superclasses_accessors.items():
+            # Here be dragons.
+            orig_accessor = getattr(self.__class__, name, None)
+            if issubclass(
+                type(orig_accessor),
+                (ReverseOneToOneDescriptor, ForwardManyToOneDescriptor),
+            ):
+                setattr(
+                    self.__class__,
+                    name,
+                    property(create_accessor_function_for_model(model, name)),
+                )
+
+    def _get_inheritance_relation_fields_and_models(self):
+        """helper function for __init__:
+        determine names of all Django inheritance accessor member functions for type(self)"""
+
+        def add_model(model, field_name, result):
+            result[field_name] = model
+
+        def add_model_if_regular(model, field_name, result):
+            if (
+                issubclass(model, models.Model)
+                and model != models.Model
+                and model != self.__class__
+                and model != PolymorphicModel
+            ):
+                add_model(model, field_name, result)
+
+        def add_all_super_models(model, result):
+            for super_cls, field_to_super in model._meta.parents.items():
+                if field_to_super is not None:
+                    # if not a link to a proxy model, the field on model can have
+                    # a different name to super_cls._meta.module_name, when the field
+                    # is created manually using 'parent_link'
+                    field_name = field_to_super.name
+                    add_model_if_regular(super_cls, field_name, result)
+                    add_all_super_models(super_cls, result)
+
+        def add_all_sub_models(super_cls, result):
+            # go through all subclasses of model
+            for sub_cls in super_cls.__subclasses__():
+                # super_cls may not be in sub_cls._meta.parents if super_cls is a proxy model
+                if super_cls in sub_cls._meta.parents:
+                    # get the field that links sub_cls to super_cls
+                    field_to_super = sub_cls._meta.parents[super_cls]
+                    # if filed_to_super is not a link to a proxy model
+                    if field_to_super is not None:
+                        super_to_sub_related_field = field_to_super.remote_field
+                        if super_to_sub_related_field.related_name is None:
+                            # if related name is None the related field is the name of the subclass
+                            to_subclass_fieldname = sub_cls.__name__.lower()
+                        else:
+                            # otherwise use the given related name
+                            to_subclass_fieldname = (
+                                super_to_sub_related_field.related_name
+                            )
+
+                        add_model_if_regular(sub_cls, to_subclass_fieldname, result)
+
+        result = {}
+        add_all_super_models(self.__class__, result)
+        add_all_sub_models(self.__class__, result)
+        return result

venv/lib/python3.8/site-packages/polymorphic/query.py

@@ -0,0 +1,527 @@
+# -*- coding: utf-8 -*-
+"""
+QuerySet for PolymorphicModel
+"""
+from __future__ import absolute_import
+
+import copy
+from collections import defaultdict
+
+from django.contrib.contenttypes.models import ContentType
+from django.db.models import FieldDoesNotExist
+from django.db.models.query import ModelIterable, Q, QuerySet
+
+from . import compat
+from .query_translate import (
+    translate_polymorphic_field_path,
+    translate_polymorphic_filter_definitions_in_args,
+    translate_polymorphic_filter_definitions_in_kwargs,
+    translate_polymorphic_Q_object,
+)
+
+# chunk-size: maximum number of objects requested per db-request
+# by the polymorphic queryset.iterator() implementation
+Polymorphic_QuerySet_objects_per_request = 100
+
+
+class PolymorphicModelIterable(ModelIterable):
+    """
+    ModelIterable for PolymorphicModel
+
+    Yields real instances if qs.polymorphic_disabled is False,
+    otherwise acts like a regular ModelIterable.
+    """
+
+    def __iter__(self):
+        base_iter = super(PolymorphicModelIterable, self).__iter__()
+        if self.queryset.polymorphic_disabled:
+            return base_iter
+        return self._polymorphic_iterator(base_iter)
+
+    def _polymorphic_iterator(self, base_iter):
+        """
+        Here we do the same as::
+
+            real_results = queryset._get_real_instances(list(base_iter))
+            for o in real_results: yield o
+
+        but it requests the objects in chunks from the database,
+        with Polymorphic_QuerySet_objects_per_request per chunk
+        """
+        while True:
+            base_result_objects = []
+            reached_end = False
+
+            # Make sure the base iterator is read in chunks instead of
+            # reading it completely, in case our caller read only a few objects.
+            for i in range(Polymorphic_QuerySet_objects_per_request):
+
+                try:
+                    o = next(base_iter)
+                    base_result_objects.append(o)
+                except StopIteration:
+                    reached_end = True
+                    break
+
+            real_results = self.queryset._get_real_instances(base_result_objects)
+
+            for o in real_results:
+                yield o
+
+            if reached_end:
+                return
+
+
+def transmogrify(cls, obj):
+    """
+    Upcast a class to a different type without asking questions.
+    """
+    if "__init__" not in obj.__dict__:
+        # Just assign __class__ to a different value.
+        new = obj
+        new.__class__ = cls
+    else:
+        # Run constructor, reassign values
+        new = cls()
+        for k, v in obj.__dict__.items():
+            new.__dict__[k] = v
+    return new
+
+
+###################################################################################
+# PolymorphicQuerySet
+
+
+class PolymorphicQuerySet(QuerySet):
+    """
+    QuerySet for PolymorphicModel
+
+    Contains the core functionality for PolymorphicModel
+
+    Usually not explicitly needed, except if a custom queryset class
+    is to be used.
+    """
+
+    def __init__(self, *args, **kwargs):
+        super(PolymorphicQuerySet, self).__init__(*args, **kwargs)
+        self._iterable_class = PolymorphicModelIterable
+
+        self.polymorphic_disabled = False
+        # A parallel structure to django.db.models.query.Query.deferred_loading,
+        # which we maintain with the untranslated field names passed to
+        # .defer() and .only() in order to be able to retranslate them when
+        # retrieving the real instance (so that the deferred fields apply
+        # to that queryset as well).
+        self.polymorphic_deferred_loading = (set([]), True)
+
+    def _clone(self, *args, **kwargs):
+        # Django's _clone only copies its own variables, so we need to copy ours here
+        new = super(PolymorphicQuerySet, self)._clone(*args, **kwargs)
+        new.polymorphic_disabled = self.polymorphic_disabled
+        new.polymorphic_deferred_loading = (
+            copy.copy(self.polymorphic_deferred_loading[0]),
+            self.polymorphic_deferred_loading[1],
+        )
+        return new
+
+    def as_manager(cls):
+        from .managers import PolymorphicManager
+
+        manager = PolymorphicManager.from_queryset(cls)()
+        manager._built_with_as_manager = True
+        return manager
+
+    as_manager.queryset_only = True
+    as_manager = classmethod(as_manager)
+
+    def bulk_create(self, objs, batch_size=None):
+        objs = list(objs)
+        for obj in objs:
+            obj.pre_save_polymorphic()
+        return super(PolymorphicQuerySet, self).bulk_create(objs, batch_size)
+
+    def non_polymorphic(self):
+        """switch off polymorphic behaviour for this query.
+        When the queryset is evaluated, only objects of the type of the
+        base class used for this query are returned."""
+        qs = self._clone()
+        qs.polymorphic_disabled = True
+        if issubclass(qs._iterable_class, PolymorphicModelIterable):
+            qs._iterable_class = ModelIterable
+        return qs
+
+    def instance_of(self, *args):
+        """Filter the queryset to only include the classes in args (and their subclasses)."""
+        # Implementation in _translate_polymorphic_filter_defnition.
+        return self.filter(instance_of=args)
+
+    def not_instance_of(self, *args):
+        """Filter the queryset to exclude the classes in args (and their subclasses)."""
+        # Implementation in _translate_polymorphic_filter_defnition."""
+        return self.filter(not_instance_of=args)
+
+    def _filter_or_exclude(self, negate, *args, **kwargs):
+        # We override this internal Django functon as it is used for all filter member functions.
+        q_objects = translate_polymorphic_filter_definitions_in_args(
+            self.model, args, using=self.db
+        )
+        # filter_field='data'
+        additional_args = translate_polymorphic_filter_definitions_in_kwargs(
+            self.model, kwargs, using=self.db
+        )
+        return super(PolymorphicQuerySet, self)._filter_or_exclude(
+            negate, *(list(q_objects) + additional_args), **kwargs
+        )
+
+    def order_by(self, *field_names):
+        """translate the field paths in the args, then call vanilla order_by."""
+        field_names = [
+            translate_polymorphic_field_path(self.model, a)
+            if isinstance(a, compat.string_types)
+            else a  # allow expressions to pass unchanged
+            for a in field_names
+        ]
+        return super(PolymorphicQuerySet, self).order_by(*field_names)
+
+    def defer(self, *fields):
+        """
+        Translate the field paths in the args, then call vanilla defer.
+
+        Also retain a copy of the original fields passed, which we'll need
+        when we're retrieving the real instance (since we'll need to translate
+        them again, as the model will have changed).
+        """
+        new_fields = [translate_polymorphic_field_path(self.model, a) for a in fields]
+        clone = super(PolymorphicQuerySet, self).defer(*new_fields)
+        clone._polymorphic_add_deferred_loading(fields)
+        return clone
+
+    def only(self, *fields):
+        """
+        Translate the field paths in the args, then call vanilla only.
+
+        Also retain a copy of the original fields passed, which we'll need
+        when we're retrieving the real instance (since we'll need to translate
+        them again, as the model will have changed).
+        """
+        new_fields = [translate_polymorphic_field_path(self.model, a) for a in fields]
+        clone = super(PolymorphicQuerySet, self).only(*new_fields)
+        clone._polymorphic_add_immediate_loading(fields)
+        return clone
+
+    def _polymorphic_add_deferred_loading(self, field_names):
+        """
+        Follows the logic of django.db.models.query.Query.add_deferred_loading(),
+        but for the non-translated field names that were passed to self.defer().
+        """
+        existing, defer = self.polymorphic_deferred_loading
+        if defer:
+            # Add to existing deferred names.
+            self.polymorphic_deferred_loading = existing.union(field_names), True
+        else:
+            # Remove names from the set of any existing "immediate load" names.
+            self.polymorphic_deferred_loading = existing.difference(field_names), False
+
+    def _polymorphic_add_immediate_loading(self, field_names):
+        """
+        Follows the logic of django.db.models.query.Query.add_immediate_loading(),
+        but for the non-translated field names that were passed to self.only()
+        """
+        existing, defer = self.polymorphic_deferred_loading
+        field_names = set(field_names)
+        if "pk" in field_names:
+            field_names.remove("pk")
+            field_names.add(self.model._meta.pk.name)
+
+        if defer:
+            # Remove any existing deferred names from the current set before
+            # setting the new names.
+            self.polymorphic_deferred_loading = field_names.difference(existing), False
+        else:
+            # Replace any existing "immediate load" field names.
+            self.polymorphic_deferred_loading = field_names, False
+
+    def _process_aggregate_args(self, args, kwargs):
+        """for aggregate and annotate kwargs: allow ModelX___field syntax for kwargs, forbid it for args.
+        Modifies kwargs if needed (these are Aggregate objects, we translate the lookup member variable)"""
+        ___lookup_assert_msg = "PolymorphicModel: annotate()/aggregate(): ___ model lookup supported for keyword arguments only"
+
+        def patch_lookup(a):
+            # The field on which the aggregate operates is
+            # stored inside a complex query expression.
+            if isinstance(a, Q):
+                translate_polymorphic_Q_object(self.model, a)
+            elif hasattr(a, "get_source_expressions"):
+                for source_expression in a.get_source_expressions():
+                    if source_expression is not None:
+                        patch_lookup(source_expression)
+            else:
+                a.name = translate_polymorphic_field_path(self.model, a.name)
+
+        def test___lookup(a):
+            """ *args might be complex expressions too in django 1.8 so
+            the testing for a '___' is rather complex on this one """
+            if isinstance(a, Q):
+
+                def tree_node_test___lookup(my_model, node):
+                    " process all children of this Q node "
+                    for i in range(len(node.children)):
+                        child = node.children[i]
+
+                        if type(child) == tuple:
+                            # this Q object child is a tuple => a kwarg like Q( instance_of=ModelB )
+                            assert "___" not in child[0], ___lookup_assert_msg
+                        else:
+                            # this Q object child is another Q object, recursively process this as well
+                            tree_node_test___lookup(my_model, child)
+
+                tree_node_test___lookup(self.model, a)
+            elif hasattr(a, "get_source_expressions"):
+                for source_expression in a.get_source_expressions():
+                    test___lookup(source_expression)
+            else:
+                assert "___" not in a.name, ___lookup_assert_msg
+
+        for a in args:
+            test___lookup(a)
+        for a in kwargs.values():
+            patch_lookup(a)
+
+    def annotate(self, *args, **kwargs):
+        """translate the polymorphic field paths in the kwargs, then call vanilla annotate.
+        _get_real_instances will do the rest of the job after executing the query."""
+        self._process_aggregate_args(args, kwargs)
+        return super(PolymorphicQuerySet, self).annotate(*args, **kwargs)
+
+    def aggregate(self, *args, **kwargs):
+        """translate the polymorphic field paths in the kwargs, then call vanilla aggregate.
+        We need no polymorphic object retrieval for aggregate => switch it off."""
+        self._process_aggregate_args(args, kwargs)
+        qs = self.non_polymorphic()
+        return super(PolymorphicQuerySet, qs).aggregate(*args, **kwargs)
+
+    # Starting with Django 1.9, the copy returned by 'qs.values(...)' has the
+    # same class as 'qs', so our polymorphic modifications would apply.
+    # We want to leave values queries untouched, so we set 'polymorphic_disabled'.
+    def _values(self, *args, **kwargs):
+        clone = super(PolymorphicQuerySet, self)._values(*args, **kwargs)
+        clone.polymorphic_disabled = True
+        return clone
+
+    # Since django_polymorphic 'V1.0 beta2', extra() always returns polymorphic results.
+    # The resulting objects are required to have a unique primary key within the result set
+    # (otherwise an error is thrown).
+    # The "polymorphic" keyword argument is not supported anymore.
+    # def extra(self, *args, **kwargs):
+
+    def _get_real_instances(self, base_result_objects):
+        """
+        Polymorphic object loader
+
+        Does the same as:
+
+            return [ o.get_real_instance() for o in base_result_objects ]
+
+        but more efficiently.
+
+        The list base_result_objects contains the objects from the executed
+        base class query. The class of all of them is self.model (our base model).
+
+        Some, many or all of these objects were not created and stored as
+        class self.model, but as a class derived from self.model. We want to re-fetch
+        these objects from the db as their original class so we can return them
+        just as they were created/saved.
+
+        We identify these objects by looking at o.polymorphic_ctype, which specifies
+        the real class of these objects (the class at the time they were saved).
+
+        First, we sort the result objects in base_result_objects for their
+        subclass (from o.polymorphic_ctype), and then we execute one db query per
+        subclass of objects. Here, we handle any annotations from annotate().
+
+        Finally we re-sort the resulting objects into the correct order and
+        return them as a list.
+        """
+        resultlist = []  # polymorphic list of result-objects
+
+        # dict contains one entry per unique model type occurring in result,
+        # in the format idlist_per_model[modelclass]=[list-of-object-ids]
+        idlist_per_model = defaultdict(list)
+        indexlist_per_model = defaultdict(list)
+
+        # django's automatic ".pk" field does not always work correctly for
+        # custom fields in derived objects (unclear yet who to put the blame on).
+        # We get different type(o.pk) in this case.
+        # We work around this by using the real name of the field directly
+        # for accessing the primary key of the the derived objects.
+        # We might assume that self.model._meta.pk.name gives us the name of the primary key field,
+        # but it doesn't. Therefore we use polymorphic_primary_key_name, which we set up in base.py.
+        pk_name = self.model.polymorphic_primary_key_name
+
+        # - sort base_result_object ids into idlist_per_model lists, depending on their real class;
+        # - store objects that already have the correct class into "results"
+        content_type_manager = ContentType.objects.db_manager(self.db)
+        self_model_class_id = content_type_manager.get_for_model(
+            self.model, for_concrete_model=False
+        ).pk
+        self_concrete_model_class_id = content_type_manager.get_for_model(
+            self.model, for_concrete_model=True
+        ).pk
+
+        for i, base_object in enumerate(base_result_objects):
+
+            if base_object.polymorphic_ctype_id == self_model_class_id:
+                # Real class is exactly the same as base class, go straight to results
+                resultlist.append(base_object)
+            else:
+                real_concrete_class = base_object.get_real_instance_class()
+                real_concrete_class_id = (
+                    base_object.get_real_concrete_instance_class_id()
+                )
+
+                if real_concrete_class_id is None:
+                    # Dealing with a stale content type
+                    continue
+                elif real_concrete_class_id == self_concrete_model_class_id:
+                    # Real and base classes share the same concrete ancestor,
+                    # upcast it and put it in the results
+                    resultlist.append(transmogrify(real_concrete_class, base_object))
+                else:
+                    # This model has a concrete derived class, track it for bulk retrieval.
+                    real_concrete_class = content_type_manager.get_for_id(
+                        real_concrete_class_id
+                    ).model_class()
+                    idlist_per_model[real_concrete_class].append(
+                        getattr(base_object, pk_name)
+                    )
+                    indexlist_per_model[real_concrete_class].append(
+                        (i, len(resultlist))
+                    )
+                    resultlist.append(None)
+
+        # For each model in "idlist_per_model" request its objects (the real model)
+        # from the db and store them in results[].
+        # Then we copy the annotate fields from the base objects to the real objects.
+        # Then we copy the extra() select fields from the base objects to the real objects.
+        # TODO: defer(), only(): support for these would be around here
+        for real_concrete_class, idlist in idlist_per_model.items():
+            indices = indexlist_per_model[real_concrete_class]
+            real_objects = real_concrete_class._base_objects.db_manager(self.db).filter(
+                **{("%s__in" % pk_name): idlist}
+            )
+            # copy select related configuration to new qs
+            real_objects.query.select_related = self.query.select_related
+
+            # Copy deferred fields configuration to the new queryset
+            deferred_loading_fields = []
+            existing_fields = self.polymorphic_deferred_loading[0]
+            for field in existing_fields:
+                try:
+                    translated_field_name = translate_polymorphic_field_path(
+                        real_concrete_class, field
+                    )
+                except AssertionError:
+                    if "___" in field:
+                        # The originally passed argument to .defer() or .only()
+                        # was in the form Model2B___field2, where Model2B is
+                        # now a superclass of real_concrete_class. Thus it's
+                        # sufficient to just use the field name.
+                        translated_field_name = field.rpartition("___")[-1]
+
+                        # Check if the field does exist.
+                        # Ignore deferred fields that don't exist in this subclass type.
+                        try:
+                            real_concrete_class._meta.get_field(translated_field_name)
+                        except FieldDoesNotExist:
+                            continue
+                    else:
+                        raise
+
+                deferred_loading_fields.append(translated_field_name)
+            real_objects.query.deferred_loading = (
+                set(deferred_loading_fields),
+                self.query.deferred_loading[1],
+            )
+
+            real_objects_dict = {
+                getattr(real_object, pk_name): real_object
+                for real_object in real_objects
+            }
+
+            for i, j in indices:
+                base_object = base_result_objects[i]
+                o_pk = getattr(base_object, pk_name)
+                real_object = real_objects_dict.get(o_pk)
+                if real_object is None:
+                    continue
+
+                # need shallow copy to avoid duplication in caches (see PR #353)
+                real_object = copy.copy(real_object)
+                real_class = real_object.get_real_instance_class()
+
+                # If the real class is a proxy, upcast it
+                if real_class != real_concrete_class:
+                    real_object = transmogrify(real_class, real_object)
+
+                if self.query.annotations:
+                    for anno_field_name in self.query.annotations.keys():
+                        attr = getattr(base_object, anno_field_name)
+                        setattr(real_object, anno_field_name, attr)
+
+                if self.query.extra_select:
+                    for select_field_name in self.query.extra_select.keys():
+                        attr = getattr(base_object, select_field_name)
+                        setattr(real_object, select_field_name, attr)
+
+                resultlist[j] = real_object
+
+        resultlist = [i for i in resultlist if i]
+
+        # set polymorphic_annotate_names in all objects (currently just used for debugging/printing)
+        if self.query.annotations:
+            # get annotate field list
+            annotate_names = list(self.query.annotations.keys())
+            for real_object in resultlist:
+                real_object.polymorphic_annotate_names = annotate_names
+
+        # set polymorphic_extra_select_names in all objects (currently just used for debugging/printing)
+        if self.query.extra_select:
+            # get extra select field list
+            extra_select_names = list(self.query.extra_select.keys())
+            for real_object in resultlist:
+                real_object.polymorphic_extra_select_names = extra_select_names
+
+        return resultlist
+
+    def __repr__(self, *args, **kwargs):
+        if self.model.polymorphic_query_multiline_output:
+            result = [repr(o) for o in self.all()]
+            return "[ " + ",\n  ".join(result) + " ]"
+        else:
+            return super(PolymorphicQuerySet, self).__repr__(*args, **kwargs)
+
+    class _p_list_class(list):
+        def __repr__(self, *args, **kwargs):
+            result = [repr(o) for o in self]
+            return "[ " + ",\n  ".join(result) + " ]"
+
+    def get_real_instances(self, base_result_objects=None):
+        """
+        Cast a list of objects to their actual classes.
+
+        This does roughly the same as::
+
+            return [ o.get_real_instance() for o in base_result_objects ]
+
+        but more efficiently.
+
+        :rtype: PolymorphicQuerySet
+        """
+        "same as _get_real_instances, but make sure that __repr__ for ShowField... creates correct output"
+        if base_result_objects is None:
+            base_result_objects = self
+        olist = self._get_real_instances(base_result_objects)
+        if not self.model.polymorphic_query_multiline_output:
+            return olist
+        clist = PolymorphicQuerySet._p_list_class(olist)
+        return clist

venv/lib/python3.8/site-packages/polymorphic/query_translate.py

@@ -0,0 +1,313 @@
+# -*- coding: utf-8 -*-
+"""
+PolymorphicQuerySet support functions
+"""
+from __future__ import absolute_import
+
+import copy
+from collections import deque
+
+from django.apps import apps
+from django.contrib.contenttypes.models import ContentType
+from django.core.exceptions import FieldError
+from django.db import models
+from django.db.models import Q
+from django.db.models.fields.related import ForeignObjectRel, RelatedField
+from django.db.utils import DEFAULT_DB_ALIAS
+
+# These functions implement the additional filter- and Q-object functionality.
+# They form a kind of small framework for easily adding more
+# functionality to filters and Q objects.
+# Probably a more general queryset enhancement class could be made out of them.
+from polymorphic import compat
+
+###################################################################################
+# PolymorphicQuerySet support functions
+
+
+def translate_polymorphic_filter_definitions_in_kwargs(
+    queryset_model, kwargs, using=DEFAULT_DB_ALIAS
+):
+    """
+    Translate the keyword argument list for PolymorphicQuerySet.filter()
+
+    Any kwargs with special polymorphic functionality are replaced in the kwargs
+    dict with their vanilla django equivalents.
+
+    For some kwargs a direct replacement is not possible, as a Q object is needed
+    instead to implement the required functionality. In these cases the kwarg is
+    deleted from the kwargs dict and a Q object is added to the return list.
+
+    Modifies: kwargs dict
+    Returns: a list of non-keyword-arguments (Q objects) to be added to the filter() query.
+    """
+    additional_args = []
+    for field_path, val in kwargs.copy().items():  # Python 3 needs copy
+
+        new_expr = _translate_polymorphic_filter_definition(
+            queryset_model, field_path, val, using=using
+        )
+
+        if type(new_expr) == tuple:
+            # replace kwargs element
+            del kwargs[field_path]
+            kwargs[new_expr[0]] = new_expr[1]
+
+        elif isinstance(new_expr, models.Q):
+            del kwargs[field_path]
+            additional_args.append(new_expr)
+
+    return additional_args
+
+
+def translate_polymorphic_Q_object(
+    queryset_model, potential_q_object, using=DEFAULT_DB_ALIAS
+):
+    def tree_node_correct_field_specs(my_model, node):
+        " process all children of this Q node "
+        for i in range(len(node.children)):
+            child = node.children[i]
+
+            if type(child) == tuple:
+                # this Q object child is a tuple => a kwarg like Q( instance_of=ModelB )
+                key, val = child
+                new_expr = _translate_polymorphic_filter_definition(
+                    my_model, key, val, using=using
+                )
+                if new_expr:
+                    node.children[i] = new_expr
+            else:
+                # this Q object child is another Q object, recursively process this as well
+                tree_node_correct_field_specs(my_model, child)
+
+    if isinstance(potential_q_object, models.Q):
+        tree_node_correct_field_specs(queryset_model, potential_q_object)
+
+    return potential_q_object
+
+
+def translate_polymorphic_filter_definitions_in_args(
+    queryset_model, args, using=DEFAULT_DB_ALIAS
+):
+    """
+    Translate the non-keyword argument list for PolymorphicQuerySet.filter()
+
+    In the args list, we return all kwargs to Q-objects that contain special
+    polymorphic functionality with their vanilla django equivalents.
+    We traverse the Q object tree for this (which is simple).
+
+
+    Returns: modified Q objects
+    """
+    return [
+        translate_polymorphic_Q_object(queryset_model, copy.deepcopy(q), using=using)
+        for q in args
+    ]
+
+
+def _translate_polymorphic_filter_definition(
+    queryset_model, field_path, field_val, using=DEFAULT_DB_ALIAS
+):
+    """
+    Translate a keyword argument (field_path=field_val), as used for
+    PolymorphicQuerySet.filter()-like functions (and Q objects).
+
+    A kwarg with special polymorphic functionality is translated into
+    its vanilla django equivalent, which is returned, either as tuple
+    (field_path, field_val) or as Q object.
+
+    Returns: kwarg tuple or Q object or None (if no change is required)
+    """
+
+    # handle instance_of expressions or alternatively,
+    # if this is a normal Django filter expression, return None
+    if field_path == "instance_of":
+        return create_instanceof_q(field_val, using=using)
+    elif field_path == "not_instance_of":
+        return create_instanceof_q(field_val, not_instance_of=True, using=using)
+    elif "___" not in field_path:
+        return None  # no change
+
+    # filter expression contains '___' (i.e. filter for polymorphic field)
+    # => get the model class specified in the filter expression
+    newpath = translate_polymorphic_field_path(queryset_model, field_path)
+    return (newpath, field_val)
+
+
+def translate_polymorphic_field_path(queryset_model, field_path):
+    """
+    Translate a field path from a keyword argument, as used for
+    PolymorphicQuerySet.filter()-like functions (and Q objects).
+    Supports leading '-' (for order_by args).
+
+    E.g.: if queryset_model is ModelA, then "ModelC___field3" is translated
+    into modela__modelb__modelc__field3.
+    Returns: translated path (unchanged, if no translation needed)
+    """
+    if not isinstance(field_path, compat.string_types):
+        raise ValueError("Expected field name as string: {0}".format(field_path))
+
+    classname, sep, pure_field_path = field_path.partition("___")
+    if not sep:
+        return field_path
+    assert classname, "PolymorphicModel: %s: bad field specification" % field_path
+
+    negated = False
+    if classname[0] == "-":
+        negated = True
+        classname = classname.lstrip("-")
+
+    if "__" in classname:
+        # the user has app label prepended to class name via __ => use Django's get_model function
+        appname, sep, classname = classname.partition("__")
+        model = apps.get_model(appname, classname)
+        assert model, "PolymorphicModel: model %s (in app %s) not found!" % (
+            model.__name__,
+            appname,
+        )
+        if not issubclass(model, queryset_model):
+            e = (
+                'PolymorphicModel: queryset filter error: "'
+                + model.__name__
+                + '" is not derived from "'
+                + queryset_model.__name__
+                + '"'
+            )
+            raise AssertionError(e)
+
+    else:
+        # the user has only given us the class name via ___
+        # => select the model from the sub models of the queryset base model
+
+        # Test whether it's actually a regular relation__ _fieldname (the field starting with an _)
+        # so no tripple ClassName___field was intended.
+        try:
+            # This also retreives M2M relations now (including reverse foreign key relations)
+            field = queryset_model._meta.get_field(classname)
+
+            if isinstance(field, (RelatedField, ForeignObjectRel)):
+                # Can also test whether the field exists in the related object to avoid ambiguity between
+                # class names and field names, but that never happens when your class names are in CamelCase.
+                return field_path  # No exception raised, field does exist.
+        except models.FieldDoesNotExist:
+            pass
+
+        submodels = _get_all_sub_models(queryset_model)
+        model = submodels.get(classname, None)
+        assert model, "PolymorphicModel: model %s not found (not a subclass of %s)!" % (
+            classname,
+            queryset_model.__name__,
+        )
+
+    basepath = _create_base_path(queryset_model, model)
+
+    if negated:
+        newpath = "-"
+    else:
+        newpath = ""
+
+    newpath += basepath
+    if basepath:
+        newpath += "__"
+
+    newpath += pure_field_path
+    return newpath
+
+
+def _get_all_sub_models(base_model):
+    """#Collect all sub-models, this should be optimized (cached)"""
+    result = {}
+    queue = deque([base_model])
+
+    while queue:
+        model = queue.popleft()
+        if issubclass(model, models.Model) and model != models.Model:
+            # model name is occurring twice in submodel inheritance tree => Error
+            if model.__name__ in result and model != result[model.__name__]:
+                raise FieldError(
+                    "PolymorphicModel: model name alone is ambiguous: %s.%s and %s.%s match!\n"
+                    "In this case, please use the syntax: applabel__ModelName___field"
+                    % (
+                        model._meta.app_label,
+                        model.__name__,
+                        result[model.__name__]._meta.app_label,
+                        result[model.__name__].__name__,
+                    )
+                )
+
+            result[model.__name__] = model
+        queue.extend(model.__subclasses__())
+
+    return result
+
+
+def _create_base_path(baseclass, myclass):
+    # create new field path for expressions, e.g. for baseclass=ModelA, myclass=ModelC
+    # 'modelb__modelc" is returned
+    for b in myclass.__bases__:
+        if b == baseclass:
+            return _get_query_related_name(myclass)
+
+        path = _create_base_path(baseclass, b)
+        if path:
+            if b._meta.abstract or b._meta.proxy:
+                return _get_query_related_name(myclass)
+            else:
+                return path + "__" + _get_query_related_name(myclass)
+    return ""
+
+
+def _get_query_related_name(myclass):
+    for f in myclass._meta.local_fields:
+        if isinstance(f, models.OneToOneField) and f.remote_field.parent_link:
+            return f.related_query_name()
+
+    # Fallback to undetected name,
+    # this happens on proxy models (e.g. SubclassSelectorProxyModel)
+    return myclass.__name__.lower()
+
+
+def create_instanceof_q(modellist, not_instance_of=False, using=DEFAULT_DB_ALIAS):
+    """
+    Helper function for instance_of / not_instance_of
+    Creates and returns a Q object that filters for the models in modellist,
+    including all subclasses of these models (as we want to do the same
+    as pythons isinstance() ).
+    .
+    We recursively collect all __subclasses__(), create a Q filter for each,
+    and or-combine these Q objects. This could be done much more
+    efficiently however (regarding the resulting sql), should an optimization
+    be needed.
+    """
+    if not modellist:
+        return None
+
+    if not isinstance(modellist, (list, tuple)):
+        from .models import PolymorphicModel
+
+        if issubclass(modellist, PolymorphicModel):
+            modellist = [modellist]
+        else:
+            raise TypeError(
+                "PolymorphicModel: instance_of expects a list of (polymorphic) "
+                "models or a single (polymorphic) model"
+            )
+
+    contenttype_ids = _get_mro_content_type_ids(modellist, using)
+    q = Q(polymorphic_ctype__in=sorted(contenttype_ids))
+    if not_instance_of:
+        q = ~q
+    return q
+
+
+def _get_mro_content_type_ids(models, using):
+    contenttype_ids = set()
+    for model in models:
+        ct = ContentType.objects.db_manager(using).get_for_model(
+            model, for_concrete_model=False
+        )
+        contenttype_ids.add(ct.pk)
+        subclasses = model.__subclasses__()
+        if subclasses:
+            contenttype_ids.update(_get_mro_content_type_ids(subclasses, using))
+    return contenttype_ids

venv/lib/python3.8/site-packages/polymorphic/showfields.py

@@ -0,0 +1,190 @@
+# -*- coding: utf-8 -*-
+import re
+
+from django.db import models
+
+from . import compat
+from .compat import python_2_unicode_compatible
+
+RE_DEFERRED = re.compile("_Deferred_.*")
+
+
+@python_2_unicode_compatible
+class ShowFieldBase(object):
+    """ base class for the ShowField... model mixins, does the work """
+
+    # cause nicer multiline PolymorphicQuery output
+    polymorphic_query_multiline_output = True
+
+    polymorphic_showfield_type = False
+    polymorphic_showfield_content = False
+    polymorphic_showfield_deferred = False
+
+    # these may be overridden by the user
+    polymorphic_showfield_max_line_width = None
+    polymorphic_showfield_max_field_width = 20
+    polymorphic_showfield_old_format = False
+
+    def __repr__(self):
+        return self.__str__()
+
+    def _showfields_get_content(self, field_name, field_type=type(None)):
+        "helper for __unicode__"
+        content = getattr(self, field_name)
+        if self.polymorphic_showfield_old_format:
+            out = ": "
+        else:
+            out = " "
+        if issubclass(field_type, models.ForeignKey):
+            if content is None:
+                out += "None"
+            else:
+                out += content.__class__.__name__
+        elif issubclass(field_type, models.ManyToManyField):
+            out += "%d" % content.count()
+        elif isinstance(content, compat.integer_types):
+            out += str(content)
+        elif content is None:
+            out += "None"
+        else:
+            txt = str(content)
+            if len(txt) > self.polymorphic_showfield_max_field_width:
+                txt = txt[: self.polymorphic_showfield_max_field_width - 2] + ".."
+            out += '"' + txt + '"'
+        return out
+
+    def _showfields_add_regular_fields(self, parts):
+        "helper for __unicode__"
+        done_fields = set()
+        for field in self._meta.fields + self._meta.many_to_many:
+            if (
+                field.name in self.polymorphic_internal_model_fields
+                or "_ptr" in field.name
+            ):
+                continue
+            if field.name in done_fields:
+                continue  # work around django diamond inheritance problem
+            done_fields.add(field.name)
+
+            out = field.name
+
+            # if this is the standard primary key named "id", print it as we did with older versions of django_polymorphic
+            if (
+                field.primary_key
+                and field.name == "id"
+                and type(field) == models.AutoField
+            ):
+                out += " " + str(getattr(self, field.name))
+
+            # otherwise, display it just like all other fields (with correct type, shortened content etc.)
+            else:
+                if self.polymorphic_showfield_type:
+                    out += " (" + type(field).__name__
+                    if field.primary_key:
+                        out += "/pk"
+                    out += ")"
+
+                if self.polymorphic_showfield_content:
+                    out += self._showfields_get_content(field.name, type(field))
+
+            parts.append((False, out, ","))
+
+    def _showfields_add_dynamic_fields(self, field_list, title, parts):
+        "helper for __unicode__"
+        parts.append((True, "- " + title, ":"))
+        for field_name in field_list:
+            out = field_name
+            content = getattr(self, field_name)
+            if self.polymorphic_showfield_type:
+                out += " (" + type(content).__name__ + ")"
+            if self.polymorphic_showfield_content:
+                out += self._showfields_get_content(field_name)
+
+            parts.append((False, out, ","))
+
+    def __str__(self):
+        # create list ("parts") containing one tuple for each title/field:
+        # ( bool: new section , item-text , separator to use after item )
+
+        # start with model name
+        parts = [(True, RE_DEFERRED.sub("", self.__class__.__name__), ":")]
+
+        # add all regular fields
+        self._showfields_add_regular_fields(parts)
+
+        # add annotate fields
+        if hasattr(self, "polymorphic_annotate_names"):
+            self._showfields_add_dynamic_fields(
+                self.polymorphic_annotate_names, "Ann", parts
+            )
+
+        # add extra() select fields
+        if hasattr(self, "polymorphic_extra_select_names"):
+            self._showfields_add_dynamic_fields(
+                self.polymorphic_extra_select_names, "Extra", parts
+            )
+
+        if self.polymorphic_showfield_deferred:
+            fields = self.get_deferred_fields()
+            if fields:
+                parts.append(
+                    (False, "deferred[{0}]".format(",".join(sorted(fields))), "")
+                )
+
+        # format result
+
+        indent = len(self.__class__.__name__) + 5
+        indentstr = "".rjust(indent)
+        out = ""
+        xpos = 0
+        possible_line_break_pos = None
+
+        for i in range(len(parts)):
+            new_section, p, separator = parts[i]
+            final = i == len(parts) - 1
+            if not final:
+                next_new_section, _, _ = parts[i + 1]
+
+            if (
+                self.polymorphic_showfield_max_line_width
+                and xpos + len(p) > self.polymorphic_showfield_max_line_width
+                and possible_line_break_pos is not None
+            ):
+                rest = out[possible_line_break_pos:]
+                out = out[:possible_line_break_pos]
+                out += "\n" + indentstr + rest
+                xpos = indent + len(rest)
+
+            out += p
+            xpos += len(p)
+
+            if not final:
+                if not next_new_section:
+                    out += separator
+                    xpos += len(separator)
+                out += " "
+                xpos += 1
+
+            if not new_section:
+                possible_line_break_pos = len(out)
+
+        return "<" + out + ">"
+
+
+class ShowFieldType(ShowFieldBase):
+    """ model mixin that shows the object's class and it's field types """
+
+    polymorphic_showfield_type = True
+
+
+class ShowFieldContent(ShowFieldBase):
+    """ model mixin that shows the object's class, it's fields and field contents """
+
+    polymorphic_showfield_content = True
+
+
+class ShowFieldTypeAndContent(ShowFieldBase):
+    """ model mixin, like ShowFieldContent, but also show field types """
+
+    polymorphic_showfield_type = True
+    polymorphic_showfield_content = True

venv/lib/python3.8/site-packages/polymorphic/static/polymorphic/css/polymorphic_inlines.css

@@ -0,0 +1,34 @@
+.polymorphic-add-choice {
+  position: relative;
+  clear: left;
+}
+
+.polymorphic-add-choice a:focus {
+  text-decoration: none;
+}
+
+.polymorphic-type-menu {
+  position: absolute;
+  top: 2.2em;
+  left: 0.5em;
+  border: 1px solid #ccc;
+  border-radius: 4px;
+  padding: 2px;
+  background-color: #fff;
+  z-index: 1000;
+}
+
+.polymorphic-type-menu ul {
+  padding: 2px;
+  margin: 0;
+}
+
+.polymorphic-type-menu li {
+  list-style: none inside none;
+  padding: 4px 8px;
+}
+
+.inline-related.empty-form {
+  /* needed for grapelli, which uses grp-empty-form */
+  display: none;
+}

venv/lib/python3.8/site-packages/polymorphic/static/polymorphic/js/polymorphic_inlines.js

@@ -0,0 +1,338 @@
+/*global DateTimeShortcuts, SelectFilter*/
+
+// This is a slightly adapted version of Django's inlines.js
+// Forked for polymorphic by Diederik van der Boor
+
+/**
+ * Django admin inlines
+ *
+ * Based on jQuery Formset 1.1
+ * @author Stanislaus Madueke (stan DOT madueke AT gmail DOT com)
+ * @requires jQuery 1.2.6 or later
+ *
+ * Copyright (c) 2009, Stanislaus Madueke
+ * All rights reserved.
+ *
+ * Spiced up with Code from Zain Memon's GSoC project 2009
+ * and modified for Django by Jannis Leidel, Travis Swicegood and Julien Phalip.
+ *
+ * Licensed under the New BSD License
+ * See: http://www.opensource.org/licenses/bsd-license.php
+ */
+(function($) {
+    'use strict';
+    $.fn.polymorphicFormset = function(opts) {
+        var options = $.extend({}, $.fn.polymorphicFormset.defaults, opts);
+        var $this = $(this);
+        var $parent = $this.parent();
+        var updateElementIndex = function(el, prefix, ndx) {
+            var id_regex = new RegExp("(" + prefix + "-(\\d+|__prefix__))");
+            var replacement = prefix + "-" + ndx;
+            if ($(el).prop("for")) {
+                $(el).prop("for", $(el).prop("for").replace(id_regex, replacement));
+            }
+            if (el.id) {
+                el.id = el.id.replace(id_regex, replacement);
+            }
+            if (el.name) {
+                el.name = el.name.replace(id_regex, replacement);
+            }
+        };
+        var totalForms = $("#id_" + options.prefix + "-TOTAL_FORMS").prop("autocomplete", "off");
+        var nextIndex = parseInt(totalForms.val(), 10);
+        var maxForms = $("#id_" + options.prefix + "-MAX_NUM_FORMS").prop("autocomplete", "off");
+        // only show the add button if we are allowed to add more items,
+        // note that max_num = None translates to a blank string.
+        var showAddButton = maxForms.val() === '' || (maxForms.val() - totalForms.val()) > 0;
+        $this.each(function(i) {
+            $(this).not("." + options.emptyCssClass).addClass(options.formCssClass);
+        });
+        if ($this.length && showAddButton) {
+            var addContainer;
+            var menuButton;
+            var addButtons;
+
+            if(options.childTypes == null) {
+              throw Error("The polymorphic fieldset options.childTypes is not defined!");
+            }
+
+            // For Polymorphic inlines, the add button opens a menu.
+            var menu = '<div class="polymorphic-type-menu" style="display: none;"><ul>';
+            for (var i = 0; i < options.childTypes.length; i++) {
+                var obj = options.childTypes[i];
+                menu += '<li><a href="#" data-type="' + obj.type + '">' + obj.name + '</a></li>';
+            }
+            menu += '</ul></div>';
+
+            if ($this.prop("tagName") === "TR") {
+                // If forms are laid out as table rows, insert the
+                // "add" button in a new table row:
+                var numCols = this.eq(-1).children().length;
+                $parent.append('<tr class="' + options.addCssClass + ' polymorphic-add-choice"><td colspan="' + numCols + '"><a href="#">' + options.addText + "</a>" + menu + "</tr>");
+                addContainer = $parent.find("tr:last > td");
+                menuButton = addContainer.children('a');
+                addButtons = addContainer.find("li a");
+            } else {
+                // Otherwise, insert it immediately after the last form:
+                $this.filter(":last").after('<div class="' + options.addCssClass + ' polymorphic-add-choice"><a href="#">' + options.addText + "</a>" + menu + "</div>");
+                addContainer = $this.filter(":last").next();
+                menuButton = addContainer.children('a');
+                addButtons = addContainer.find("li a");
+            }
+
+            menuButton.click(function(event) {
+                event.preventDefault();
+                event.stopPropagation();  // for menu hide
+                var $menu = $(event.target).next('.polymorphic-type-menu');
+
+                if(! $menu.is(':visible')) {
+                    var hideMenu = function() {
+                        $menu.slideUp(50);
+                        $(document).unbind('click', hideMenu);
+                    };
+
+                    $(document).click(hideMenu);
+                }
+
+                $menu.slideToggle(50);
+            });
+
+            addButtons.click(function(event) {
+                event.preventDefault();
+                var polymorphicType = $(event.target).attr('data-type');  // Select polymorphic type.
+                var template = $("#" + polymorphicType + "-empty");
+                var row = template.clone(true);
+                row.removeClass(options.emptyCssClass)
+                .addClass(options.formCssClass)
+                .attr("id", options.prefix + "-" + nextIndex);
+                if (row.is("tr")) {
+                    // If the forms are laid out in table rows, insert
+                    // the remove button into the last table cell:
+                    row.children(":last").append('<div><a class="' + options.deleteCssClass + '" href="#">' + options.deleteText + "</a></div>");
+                } else if (row.is("ul") || row.is("ol")) {
+                    // If they're laid out as an ordered/unordered list,
+                    // insert an <li> after the last list item:
+                    row.append('<li><a class="' + options.deleteCssClass + '" href="#">' + options.deleteText + "</a></li>");
+                } else {
+                    // Otherwise, just insert the remove button as the
+                    // last child element of the form's container:
+                    row.children(":first").append('<span><a class="' + options.deleteCssClass + '" href="#">' + options.deleteText + "</a></span>");
+                }
+                row.find("*").each(function() {
+                    updateElementIndex(this, options.prefix, totalForms.val());
+                });
+                // Insert the new form when it has been fully edited
+                row.insertBefore($(template));
+                // Update number of total forms
+                $(totalForms).val(parseInt(totalForms.val(), 10) + 1);
+                nextIndex += 1;
+                // Hide add button in case we've hit the max, except we want to add infinitely
+                if ((maxForms.val() !== '') && (maxForms.val() - totalForms.val()) <= 0) {
+                    addContainer.hide();
+                }
+                // The delete button of each row triggers a bunch of other things
+                row.find("a." + options.deleteCssClass).click(function(e1) {
+                    e1.preventDefault();
+                    // Remove the parent form containing this button:
+                    row.remove();
+                    nextIndex -= 1;
+                    // If a post-delete callback was provided, call it with the deleted form:
+                    if (options.removed) {
+                        options.removed(row);
+                    }
+                    $(document).trigger('formset:removed', [row, options.prefix]);
+                    // Update the TOTAL_FORMS form count.
+                    var forms = $("." + options.formCssClass);
+                    $("#id_" + options.prefix + "-TOTAL_FORMS").val(forms.length);
+                    // Show add button again once we drop below max
+                    if ((maxForms.val() === '') || (maxForms.val() - forms.length) > 0) {
+                        addContainer.show();
+                    }
+                    // Also, update names and ids for all remaining form controls
+                    // so they remain in sequence:
+                    var i, formCount;
+                    var updateElementCallback = function() {
+                        updateElementIndex(this, options.prefix, i);
+                    };
+                    for (i = 0, formCount = forms.length; i < formCount; i++) {
+                        updateElementIndex($(forms).get(i), options.prefix, i);
+                        $(forms.get(i)).find("*").each(updateElementCallback);
+                    }
+                });
+                // If a post-add callback was supplied, call it with the added form:
+                if (options.added) {
+                    options.added(row);
+                }
+                $(document).trigger('formset:added', [row, options.prefix]);
+            });
+        }
+        return this;
+    };
+
+    /* Setup plugin defaults */
+    $.fn.polymorphicFormset.defaults = {
+        prefix: "form",          // The form prefix for your django formset
+        addText: "add another",      // Text for the add link
+        childTypes: null,           // defined by the client.
+        deleteText: "remove",      // Text for the delete link
+        addCssClass: "add-row",      // CSS class applied to the add link
+        deleteCssClass: "delete-row",  // CSS class applied to the delete link
+        emptyCssClass: "empty-row",    // CSS class applied to the empty row
+        formCssClass: "dynamic-form",  // CSS class applied to each form in a formset
+        added: null,          // Function called each time a new form is added
+        removed: null,          // Function called each time a form is deleted
+        addButton: null       // Existing add button to use
+    };
+
+
+    // Tabular inlines ---------------------------------------------------------
+    $.fn.tabularPolymorphicFormset = function(options) {
+        var $rows = $(this);
+        var alternatingRows = function(row) {
+            $($rows.selector).not(".add-row").removeClass("row1 row2")
+            .filter(":even").addClass("row1").end()
+            .filter(":odd").addClass("row2");
+        };
+
+        var reinitDateTimeShortCuts = function() {
+            // Reinitialize the calendar and clock widgets by force
+            if (typeof DateTimeShortcuts !== "undefined") {
+                $(".datetimeshortcuts").remove();
+                DateTimeShortcuts.init();
+            }
+        };
+
+        var updateSelectFilter = function() {
+            // If any SelectFilter widgets are a part of the new form,
+            // instantiate a new SelectFilter instance for it.
+            if (typeof SelectFilter !== 'undefined') {
+                $('.selectfilter').each(function(index, value) {
+                    var namearr = value.name.split('-');
+                    SelectFilter.init(value.id, namearr[namearr.length - 1], false);
+                });
+                $('.selectfilterstacked').each(function(index, value) {
+                    var namearr = value.name.split('-');
+                    SelectFilter.init(value.id, namearr[namearr.length - 1], true);
+                });
+            }
+        };
+
+        var initPrepopulatedFields = function(row) {
+            row.find('.prepopulated_field').each(function() {
+                var field = $(this),
+                    input = field.find('input, select, textarea'),
+                    dependency_list = input.data('dependency_list') || [],
+                    dependencies = [];
+                $.each(dependency_list, function(i, field_name) {
+                    dependencies.push('#' + row.find('.field-' + field_name).find('input, select, textarea').attr('id'));
+                });
+                if (dependencies.length) {
+                    input.prepopulate(dependencies, input.attr('maxlength'));
+                }
+            });
+        };
+
+        $rows.polymorphicFormset({
+            prefix: options.prefix,
+            addText: options.addText,
+            childTypes: options.childTypes,
+            formCssClass: "dynamic-" + options.prefix,
+            deleteCssClass: "inline-deletelink",
+            deleteText: options.deleteText,
+            emptyCssClass: "empty-form",
+            removed: alternatingRows,
+            added: function(row) {
+                initPrepopulatedFields(row);
+                reinitDateTimeShortCuts();
+                updateSelectFilter();
+                alternatingRows(row);
+            },
+            addButton: options.addButton
+        });
+
+        return $rows;
+    };
+
+    // Stacked inlines ---------------------------------------------------------
+    $.fn.stackedPolymorphicFormset = function(options) {
+        var $rows = $(this);
+        var updateInlineLabel = function(row) {
+            $($rows.selector).find(".inline_label").each(function(i) {
+                var count = i + 1;
+                $(this).html($(this).html().replace(/(#\d+)/g, "#" + count));
+            });
+        };
+
+        var reinitDateTimeShortCuts = function() {
+            // Reinitialize the calendar and clock widgets by force, yuck.
+            if (typeof DateTimeShortcuts !== "undefined") {
+                $(".datetimeshortcuts").remove();
+                DateTimeShortcuts.init();
+            }
+        };
+
+        var updateSelectFilter = function() {
+            // If any SelectFilter widgets were added, instantiate a new instance.
+            if (typeof SelectFilter !== "undefined") {
+                $(".selectfilter").each(function(index, value) {
+                    var namearr = value.name.split('-');
+                    SelectFilter.init(value.id, namearr[namearr.length - 1], false);
+                });
+                $(".selectfilterstacked").each(function(index, value) {
+                    var namearr = value.name.split('-');
+                    SelectFilter.init(value.id, namearr[namearr.length - 1], true);
+                });
+            }
+        };
+
+        var initPrepopulatedFields = function(row) {
+            row.find('.prepopulated_field').each(function() {
+                var field = $(this),
+                    input = field.find('input, select, textarea'),
+                    dependency_list = input.data('dependency_list') || [],
+                    dependencies = [];
+                $.each(dependency_list, function(i, field_name) {
+                    dependencies.push('#' + row.find('.form-row .field-' + field_name).find('input, select, textarea').attr('id'));
+                });
+                if (dependencies.length) {
+                    input.prepopulate(dependencies, input.attr('maxlength'));
+                }
+            });
+        };
+
+        $rows.polymorphicFormset({
+            prefix: options.prefix,
+            addText: options.addText,
+            childTypes: options.childTypes,
+            formCssClass: "dynamic-" + options.prefix,
+            deleteCssClass: "inline-deletelink",
+            deleteText: options.deleteText,
+            emptyCssClass: "empty-form",
+            removed: updateInlineLabel,
+            added: function(row) {
+                initPrepopulatedFields(row);
+                reinitDateTimeShortCuts();
+                updateSelectFilter();
+                updateInlineLabel(row);
+            },
+            addButton: options.addButton
+        });
+
+        return $rows;
+    };
+
+    $(document).ready(function() {
+        $(".js-inline-polymorphic-admin-formset").each(function() {
+            var data = $(this).data(),
+                inlineOptions = data.inlineFormset;
+            switch(data.inlineType) {
+            case "stacked":
+                $(inlineOptions.name + "-group .inline-related").stackedPolymorphicFormset(inlineOptions.options);
+                break;
+            case "tabular":
+                $(inlineOptions.name + "-group .tabular.inline-related tbody tr").tabularPolymorphicFormset(inlineOptions.options);
+                break;
+            }
+        });
+    });
+})(django.jQuery);

venv/lib/python3.8/site-packages/polymorphic/templates/admin/polymorphic/add_type_form.html

@@ -0,0 +1,11 @@
+{% extends "admin/change_form.html" %}
+
+{% if save_on_top %}
+  {% block submit_buttons_top %}
+    {% include 'admin/submit_line.html' with show_save=1 %}
+  {% endblock %}
+{% endif %}
+
+{% block submit_buttons_bottom %}
+  {% include 'admin/submit_line.html' with show_save=1 %}
+{% endblock %}

venv/lib/python3.8/site-packages/polymorphic/templates/admin/polymorphic/change_form.html

@@ -0,0 +1,6 @@
+{% extends "admin/change_form.html" %}
+{% load polymorphic_admin_tags %}
+
+{% block breadcrumbs %}
+  {% breadcrumb_scope base_opts %}{{ block.super }}{% endbreadcrumb_scope %}
+{% endblock %}

venv/lib/python3.8/site-packages/polymorphic/templates/admin/polymorphic/delete_confirmation.html

@@ -0,0 +1,6 @@
+{% extends "admin/delete_confirmation.html" %}
+{% load polymorphic_admin_tags %}
+
+{% block breadcrumbs %}
+  {% breadcrumb_scope base_opts %}{{ block.super }}{% endbreadcrumb_scope %}
+{% endblock %}

venv/lib/python3.8/site-packages/polymorphic/templates/admin/polymorphic/edit_inline/stacked.html

@@ -0,0 +1,36 @@
+{% load i18n admin_urls static %}
+
+<div class="js-inline-polymorphic-admin-formset inline-group"
+     id="{{ inline_admin_formset.formset.prefix }}-group"
+     data-inline-type="stacked"
+     data-inline-formset="{{ inline_admin_formset.inline_formset_data }}">
+
+<fieldset class="module {{ inline_admin_formset.classes }}">
+  <h2>{{ inline_admin_formset.opts.verbose_name_plural|capfirst }}</h2>
+{{ inline_admin_formset.formset.management_form }}
+{{ inline_admin_formset.formset.non_form_errors }}
+
+{% for inline_admin_form in inline_admin_formset %}
+  <div class="inline-related inline-{{ inline_admin_form.model_admin.opts.model_name }}{% if inline_admin_form.original or inline_admin_form.show_url %} has_original{% endif %}{% if inline_admin_form.is_empty %} empty-form {% endif %}{% if forloop.last %} last-related{% endif %}"
+       id="{% if inline_admin_form.original.pk %}{{ inline_admin_formset.formset.prefix }}-{{ forloop.counter0 }}{% else %}{{ inline_admin_form.model_admin.opts.model_name }}-empty{% endif %}">
+
+    <h3><b>{{ inline_admin_form.model_admin.opts.verbose_name|capfirst }}:</b>&nbsp;<span class="inline_label">{% if inline_admin_form.original %}{{ inline_admin_form.original }}{% if inline_admin_form.model_admin.show_change_link and inline_admin_form.model_admin.has_registered_model %} <a href="{% url inline_admin_form.model_admin.opts|admin_urlname:'change' inline_admin_form.original.pk|admin_urlquote %}" class="inlinechangelink">{% trans "Change" %}</a>{% endif %}
+{% else %}#{{ forloop.counter }}{% endif %}</span>
+        {% if inline_admin_form.show_url %}<a href="{{ inline_admin_form.absolute_url }}">{% trans "View on site" %}</a>{% endif %}
+      {% if inline_admin_form.formset.can_delete and inline_admin_form.original %}<span class="delete">{{ inline_admin_form.deletion_field.field }} {{ inline_admin_form.deletion_field.label_tag }}</span>{% endif %}
+    </h3>
+
+    {% if inline_admin_form.form.non_field_errors %}{{ inline_admin_form.form.non_field_errors }}{% endif %}
+
+    {% for fieldset in inline_admin_form %}
+      {% include "admin/includes/fieldset.html" %}
+    {% endfor %}
+
+    {% if inline_admin_form.needs_explicit_pk_field %}{{ inline_admin_form.pk_field.field }}{% endif %}
+
+    {{ inline_admin_form.fk_field.field }}
+    {{ inline_admin_form.polymorphic_ctype_field.field }}
+  </div>
+{% endfor %}
+</fieldset>
+</div>

venv/lib/python3.8/site-packages/polymorphic/templates/admin/polymorphic/object_history.html

@@ -0,0 +1,6 @@
+{% extends "admin/object_history.html" %}
+{% load polymorphic_admin_tags %}
+
+{% block breadcrumbs %}
+  {% breadcrumb_scope base_opts %}{{ block.super }}{% endbreadcrumb_scope %}
+{% endblock %}

venv/lib/python3.8/site-packages/polymorphic/templatetags/__init__.py

@@ -0,0 +1,77 @@
+"""
+Template tags for polymorphic
+
+
+The ``polymorphic_formset_tags`` Library
+----------------------------------------
+
+.. versionadded:: 1.1
+
+To render formsets in the frontend, the ``polymorphic_tags`` provides extra
+filters to implement HTML rendering of polymorphic formsets.
+
+The following filters are provided;
+
+* ``{{ formset|as_script_options }}`` render the ``data-options`` for a JavaScript formset library.
+* ``{{ formset|include_empty_form }}`` provide the placeholder form for an add button.
+* ``{{ form|as_form_type }}`` return the model name that the form instance uses.
+* ``{{ model|as_model_name }}`` performs the same, for a model class or instance.
+
+.. code-block:: html+django
+
+    {% load i18n polymorphic_formset_tags %}
+
+    <div class="inline-group" id="{{ formset.prefix }}-group" data-options="{{ formset|as_script_options }}">
+        {% block add_button %}
+            {% if formset.show_add_button|default_if_none:'1' %}
+                {% if formset.empty_forms %}
+                    {# django-polymorphic formset (e.g. PolymorphicInlineFormSetView) #}
+                    <div class="btn-group" role="group">
+                      {% for model in formset.child_forms %}
+                          <a type="button" data-type="{{ model|as_model_name }}" class="js-add-form btn btn-default">{% glyphicon 'plus' %} {{ model|as_verbose_name }}</a>
+                      {% endfor %}
+                    </div>
+                {% else %}
+                    <a class="btn btn-default js-add-form">{% trans "Add" %}</a>
+                {% endif %}
+            {% endif %}
+        {% endblock %}
+
+        {{ formset.management_form }}
+
+        {% for form in formset|include_empty_form %}
+          {% block formset_form_wrapper %}
+            <div id="{{ form.prefix }}" data-inline-type="{{ form|as_form_type|lower }}" class="inline-related{% if '__prefix__' in form.prefix %} empty-form{% endif %}">
+                {{ form.non_field_errors }}
+
+                {# Add the 'pk' field that is not mentioned in crispy #}
+                {% for field in form.hidden_fields %}
+                  {{ field }}
+                {% endfor %}
+
+                {% block formset_form %}
+                    {% crispy form %}
+                {% endblock %}
+            </div>
+          {% endblock %}
+        {% endfor %}
+    </div>
+
+
+The ``polymorphic_admin_tags`` Library
+--------------------------------------
+
+The ``{% breadcrumb_scope ... %}`` tag makes sure the ``{{ opts }}`` and ``{{ app_label }}``
+values are temporary based on the provided ``{{ base_opts }}``.
+This allows fixing the breadcrumb in admin templates:
+
+.. code-block:: html+django
+
+    {% extends "admin/change_form.html" %}
+    {% load polymorphic_admin_tags %}
+
+    {% block breadcrumbs %}
+      {% breadcrumb_scope base_opts %}{{ block.super }}{% endbreadcrumb_scope %}
+    {% endblock %}
+
+"""

venv/lib/python3.8/site-packages/polymorphic/templatetags/polymorphic_admin_tags.py

@@ -0,0 +1,52 @@
+from django.template import Library, Node, TemplateSyntaxError
+
+from polymorphic import compat
+
+register = Library()
+
+
+class BreadcrumbScope(Node):
+    def __init__(self, base_opts, nodelist):
+        self.base_opts = base_opts
+        self.nodelist = nodelist  # Note, takes advantage of Node.child_nodelists
+
+    @classmethod
+    def parse(cls, parser, token):
+        bits = token.split_contents()
+        if len(bits) == 2:
+            (tagname, base_opts) = bits
+            base_opts = parser.compile_filter(base_opts)
+            nodelist = parser.parse(("endbreadcrumb_scope",))
+            parser.delete_first_token()
+
+            return cls(base_opts=base_opts, nodelist=nodelist)
+        else:
+            raise TemplateSyntaxError(
+                "{0} tag expects 1 argument".format(token.contents[0])
+            )
+
+    def render(self, context):
+        # app_label is really hard to overwrite in the standard Django ModelAdmin.
+        # To insert it in the template, the entire render_change_form() and delete_view() have to copied and adjusted.
+        # Instead, have an assignment tag that inserts that in the template.
+        base_opts = self.base_opts.resolve(context)
+        new_vars = {}
+        if base_opts and not isinstance(base_opts, compat.string_types):
+            new_vars = {
+                "app_label": base_opts.app_label,  # What this is all about
+                "opts": base_opts,
+            }
+
+        new_scope = context.push()
+        new_scope.update(new_vars)
+        html = self.nodelist.render(context)
+        context.pop()
+        return html
+
+
+@register.tag
+def breadcrumb_scope(parser, token):
+    """
+    Easily allow the breadcrumb to be generated in the admin change templates.
+    """
+    return BreadcrumbScope.parse(parser, token)

venv/lib/python3.8/site-packages/polymorphic/templatetags/polymorphic_formset_tags.py

@@ -0,0 +1,79 @@
+import json
+
+from django.template import Library
+from django.utils.encoding import force_text
+from django.utils.text import capfirst
+from django.utils.translation import ugettext
+
+from polymorphic.formsets import BasePolymorphicModelFormSet
+
+register = Library()
+
+
+@register.filter()
+def include_empty_form(formset):
+    """
+    Make sure the "empty form" is included when displaying a formset (typically table with input rows)
+    """
+    for form in formset:
+        yield form
+
+    if hasattr(formset, "empty_forms"):
+        # BasePolymorphicModelFormSet
+        for form in formset.empty_forms:
+            yield form
+    else:
+        # Standard Django formset
+        yield formset.empty_form
+
+
+@register.filter
+def as_script_options(formset):
+    """
+    A JavaScript data structure for the JavaScript code
+
+    This generates the ``data-options`` attribute for ``jquery.django-inlines.js``
+    The formset may define the following extra attributes:
+
+    - ``verbose_name``
+    - ``add_text``
+    - ``show_add_button``
+    """
+    verbose_name = getattr(formset, "verbose_name", formset.model._meta.verbose_name)
+    options = {
+        "prefix": formset.prefix,
+        "pkFieldName": formset.model._meta.pk.name,
+        "addText": getattr(formset, "add_text", None)
+        or ugettext("Add another %(verbose_name)s")
+        % {"verbose_name": capfirst(verbose_name)},
+        "showAddButton": getattr(formset, "show_add_button", True),
+        "deleteText": ugettext("Delete"),
+    }
+
+    if isinstance(formset, BasePolymorphicModelFormSet):
+        # Allow to add different types
+        options["childTypes"] = [
+            {
+                "name": force_text(model._meta.verbose_name),
+                "type": model._meta.model_name,
+            }
+            for model in formset.child_forms.keys()
+        ]
+
+    return json.dumps(options)
+
+
+@register.filter
+def as_form_type(form):
+    """
+    Usage: ``{{ form|as_form_type }}``
+    """
+    return form._meta.model._meta.model_name
+
+
+@register.filter
+def as_model_name(model):
+    """
+    Usage: ``{{ model|as_model_name }}``
+    """
+    return model._meta.model_name

venv/lib/python3.8/site-packages/polymorphic/tests/test_admin.py

@@ -0,0 +1,141 @@
+from django.contrib import admin
+from django.contrib.contenttypes.models import ContentType
+from django.utils.html import escape
+
+from polymorphic.admin import (
+    PolymorphicChildModelAdmin,
+    PolymorphicChildModelFilter,
+    PolymorphicInlineSupportMixin,
+    PolymorphicParentModelAdmin,
+    StackedPolymorphicInline,
+)
+from polymorphic.tests.admintestcase import AdminTestCase
+from polymorphic.tests.models import (
+    InlineModelA,
+    InlineModelB,
+    InlineParent,
+    Model2A,
+    Model2B,
+    Model2C,
+    Model2D,
+)
+
+
+class PolymorphicAdminTests(AdminTestCase):
+    def test_admin_registration(self):
+        """
+        Test how the registration works
+        """
+
+        @self.register(Model2A)
+        class Model2Admin(PolymorphicParentModelAdmin):
+            base_model = Model2A
+            list_filter = (PolymorphicChildModelFilter,)
+            child_models = (Model2B, Model2C, Model2D)
+
+        @self.register(Model2B)
+        @self.register(Model2C)
+        @self.register(Model2D)
+        class Model2ChildAdmin(PolymorphicChildModelAdmin):
+            base_model = Model2A
+            base_fieldsets = (("Base fields", {"fields": ("field1",)}),)
+
+        # -- add page
+        ct_id = ContentType.objects.get_for_model(Model2D).pk
+        self.admin_get_add(Model2A)  # shows type page
+        self.admin_get_add(Model2A, qs="?ct_id={}".format(ct_id))  # shows type page
+
+        self.admin_get_add(Model2A)  # shows type page
+        self.admin_post_add(
+            Model2A,
+            {"field1": "A", "field2": "B", "field3": "C", "field4": "D"},
+            qs="?ct_id={}".format(ct_id),
+        )
+
+        d_obj = Model2A.objects.all()[0]
+        self.assertEqual(d_obj.__class__, Model2D)
+        self.assertEqual(d_obj.field1, "A")
+        self.assertEqual(d_obj.field2, "B")
+
+        # -- list page
+        self.admin_get_changelist(Model2A)  # asserts 200
+
+        # -- edit
+        response = self.admin_get_change(Model2A, d_obj.pk)
+        self.assertContains(response, "field4")
+        self.admin_post_change(
+            Model2A,
+            d_obj.pk,
+            {"field1": "A2", "field2": "B2", "field3": "C2", "field4": "D2"},
+        )
+
+        d_obj.refresh_from_db()
+        self.assertEqual(d_obj.field1, "A2")
+        self.assertEqual(d_obj.field2, "B2")
+        self.assertEqual(d_obj.field3, "C2")
+        self.assertEqual(d_obj.field4, "D2")
+
+        # -- history
+        self.admin_get_history(Model2A, d_obj.pk)
+
+        # -- delete
+        self.admin_get_delete(Model2A, d_obj.pk)
+        self.admin_post_delete(Model2A, d_obj.pk)
+        self.assertRaises(Model2A.DoesNotExist, lambda: d_obj.refresh_from_db())
+
+    def test_admin_inlines(self):
+        """
+        Test the registration of inline models.
+        """
+
+        class InlineModelAChild(StackedPolymorphicInline.Child):
+            model = InlineModelA
+
+        class InlineModelBChild(StackedPolymorphicInline.Child):
+            model = InlineModelB
+
+        class Inline(StackedPolymorphicInline):
+            model = InlineModelA
+            child_inlines = (InlineModelAChild, InlineModelBChild)
+
+        @self.register(InlineParent)
+        class InlineParentAdmin(PolymorphicInlineSupportMixin, admin.ModelAdmin):
+            inlines = (Inline,)
+
+        parent = InlineParent.objects.create(title="FOO")
+        self.assertEqual(parent.inline_children.count(), 0)
+
+        # -- get edit page
+        response = self.admin_get_change(InlineParent, parent.pk)
+
+        # Make sure the fieldset has the right data exposed in data-inline-formset
+        self.assertContains(response, "childTypes")
+        self.assertContains(response, escape('"type": "inlinemodela"'))
+        self.assertContains(response, escape('"type": "inlinemodelb"'))
+
+        # -- post edit page
+        self.admin_post_change(
+            InlineParent,
+            parent.pk,
+            {
+                "title": "FOO2",
+                "inline_children-INITIAL_FORMS": 0,
+                "inline_children-TOTAL_FORMS": 1,
+                "inline_children-MIN_NUM_FORMS": 0,
+                "inline_children-MAX_NUM_FORMS": 1000,
+                "inline_children-0-parent": parent.pk,
+                "inline_children-0-polymorphic_ctype": ContentType.objects.get_for_model(
+                    InlineModelB
+                ).pk,
+                "inline_children-0-field1": "A2",
+                "inline_children-0-field2": "B2",
+            },
+        )
+
+        parent.refresh_from_db()
+        self.assertEqual(parent.title, "FOO2")
+        self.assertEqual(parent.inline_children.count(), 1)
+        child = parent.inline_children.all()[0]
+        self.assertEqual(child.__class__, InlineModelB)
+        self.assertEqual(child.field1, "A2")
+        self.assertEqual(child.field2, "B2")

venv/lib/python3.8/site-packages/polymorphic/tests/test_multidb.py

@@ -0,0 +1,130 @@
+from __future__ import print_function
+
+from django.contrib.contenttypes.models import ContentType
+from django.db.models import Q
+from django.test import TestCase
+
+from polymorphic.tests.models import (
+    Base,
+    BlogA,
+    BlogEntry,
+    Model2A,
+    Model2B,
+    Model2C,
+    Model2D,
+    ModelX,
+    ModelY,
+    One2OneRelatingModel,
+    RelatingModel,
+)
+
+
+class MultipleDatabasesTests(TestCase):
+    multi_db = True
+
+    def test_save_to_non_default_database(self):
+        Model2A.objects.db_manager("secondary").create(field1="A1")
+        Model2C(field1="C1", field2="C2", field3="C3").save(using="secondary")
+        Model2B.objects.create(field1="B1", field2="B2")
+        Model2D(field1="D1", field2="D2", field3="D3", field4="D4").save()
+
+        self.assertQuerysetEqual(
+            Model2A.objects.order_by("id"),
+            [Model2B, Model2D],
+            transform=lambda o: o.__class__,
+        )
+
+        self.assertQuerysetEqual(
+            Model2A.objects.db_manager("secondary").order_by("id"),
+            [Model2A, Model2C],
+            transform=lambda o: o.__class__,
+        )
+
+    def test_instance_of_filter_on_non_default_database(self):
+        Base.objects.db_manager("secondary").create(field_b="B1")
+        ModelX.objects.db_manager("secondary").create(field_b="B", field_x="X")
+        ModelY.objects.db_manager("secondary").create(field_b="Y", field_y="Y")
+
+        objects = Base.objects.db_manager("secondary").filter(instance_of=Base)
+        self.assertQuerysetEqual(
+            objects,
+            [Base, ModelX, ModelY],
+            transform=lambda o: o.__class__,
+            ordered=False,
+        )
+
+        self.assertQuerysetEqual(
+            Base.objects.db_manager("secondary").filter(instance_of=ModelX),
+            [ModelX],
+            transform=lambda o: o.__class__,
+        )
+
+        self.assertQuerysetEqual(
+            Base.objects.db_manager("secondary").filter(instance_of=ModelY),
+            [ModelY],
+            transform=lambda o: o.__class__,
+        )
+
+        self.assertQuerysetEqual(
+            Base.objects.db_manager("secondary").filter(
+                Q(instance_of=ModelX) | Q(instance_of=ModelY)
+            ),
+            [ModelX, ModelY],
+            transform=lambda o: o.__class__,
+            ordered=False,
+        )
+
+    def test_forward_many_to_one_descriptor_on_non_default_database(self):
+        def func():
+            blog = BlogA.objects.db_manager("secondary").create(
+                name="Blog", info="Info"
+            )
+            entry = BlogEntry.objects.db_manager("secondary").create(
+                blog=blog, text="Text"
+            )
+            ContentType.objects.clear_cache()
+            entry = BlogEntry.objects.db_manager("secondary").get(pk=entry.id)
+            self.assertEqual(blog, entry.blog)
+
+        # Ensure no queries are made using the default database.
+        self.assertNumQueries(0, func)
+
+    def test_reverse_many_to_one_descriptor_on_non_default_database(self):
+        def func():
+            blog = BlogA.objects.db_manager("secondary").create(
+                name="Blog", info="Info"
+            )
+            entry = BlogEntry.objects.db_manager("secondary").create(
+                blog=blog, text="Text"
+            )
+            ContentType.objects.clear_cache()
+            blog = BlogA.objects.db_manager("secondary").get(pk=blog.id)
+            self.assertEqual(entry, blog.blogentry_set.using("secondary").get())
+
+        # Ensure no queries are made using the default database.
+        self.assertNumQueries(0, func)
+
+    def test_reverse_one_to_one_descriptor_on_non_default_database(self):
+        def func():
+            m2a = Model2A.objects.db_manager("secondary").create(field1="A1")
+            one2one = One2OneRelatingModel.objects.db_manager("secondary").create(
+                one2one=m2a, field1="121"
+            )
+            ContentType.objects.clear_cache()
+            m2a = Model2A.objects.db_manager("secondary").get(pk=m2a.id)
+            self.assertEqual(one2one, m2a.one2onerelatingmodel)
+
+        # Ensure no queries are made using the default database.
+        self.assertNumQueries(0, func)
+
+    def test_many_to_many_descriptor_on_non_default_database(self):
+        def func():
+            m2a = Model2A.objects.db_manager("secondary").create(field1="A1")
+            rm = RelatingModel.objects.db_manager("secondary").create()
+            rm.many2many.add(m2a)
+            ContentType.objects.clear_cache()
+            m2a = Model2A.objects.db_manager("secondary").get(pk=m2a.id)
+            self.assertEqual(rm, m2a.relatingmodel_set.using("secondary").get())
+
+        # Ensure no queries are made using the default database.
+        self.assertNumQueries(0, func)