From b06d1dae4222cdb6e50fef629967bc76625b52e9 Mon Sep 17 00:00:00 2001
From: Philip Sargent <philip.sargent@klebos.com>
Date: Wed, 23 Nov 2022 10:48:39 +0000
Subject: [PATCH] Convert.format() to f-strings with flynt

---
 core/middleware.py           |  4 ++--
 core/models/caves.py         | 16 ++++++++--------
 core/models/troggle.py       | 12 ++++++------
 core/templatetags/link.py    |  2 +-
 core/utils.py                |  8 ++++----
 core/views/caves.py          | 20 ++++++++++----------
 core/views/editor_helpers.py | 10 +++++-----
 core/views/expo.py           |  4 ++--
 core/views/logbooks.py       |  2 +-
 core/views/statistics.py     | 12 ++++++------
 databaseReset.py             | 34 +++++++++++++++++-----------------
 dump.py                      |  6 +++---
 modelviz.py                  |  2 +-
 reset-django.py              |  6 +++---
 14 files changed, 69 insertions(+), 69 deletions(-)

diff --git a/core/middleware.py b/core/middleware.py
index e87662e..06c159a 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -44,11 +44,11 @@ class SmartAppendSlashMiddleware(object):
         else:          
             if settings.DEBUG and request.method == 'POST':
                 # replace this exception with a redirect to an error page
-                raise RuntimeError("You called this URL via POST, but the URL doesn't end in a slash and you have SMART_APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to %s%s (note the trailing slash), or set SMART_APPEND_SLASH=False in your Django settings." % (new_url[0], new_url[1]))
+                raise RuntimeError(f"You called this URL via POST, but the URL doesn't end in a slash and you have SMART_APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to {new_url[0]}{new_url[1]} (note the trailing slash), or set SMART_APPEND_SLASH=False in your Django settings.")
         if new_url != old_url:
             # Redirect
             if new_url[0]:
-                newurl = "%s://%s%s" % (request.is_secure() and 'https' or 'http', new_url[0], new_url[1])
+                newurl = f"{request.is_secure() and 'https' or 'http'}://{new_url[0]}{new_url[1]}"
             else:
                 newurl = new_url[1]
             if request.GET:
diff --git a/core/models/caves.py b/core/models/caves.py
index 98b4832..30a4a0b 100644
--- a/core/models/caves.py
+++ b/core/models/caves.py
@@ -144,9 +144,9 @@ class Cave(TroggleModel):
 
     def reference(self):
         if self.kataster_number:
-            return "%s-%s" % (self.kat_area(), self.kataster_number)
+            return f"{self.kat_area()}-{self.kataster_number}"
         else:
-            return "%s-%s" % (self.kat_area(), self.unofficial_number)
+            return f"{self.kat_area()}-{self.unofficial_number}"
     
     def get_absolute_url(self):
         if self.kataster_number:
@@ -332,21 +332,21 @@ class Entrance(TroggleModel):
         if self.tag_station:
             try:
                 s = SurvexStation.objects.lookup(self.tag_station)
-                return r + "%0.0fE %0.0fN %0.0fAlt" % (s.x, s.y, s.z)
+                return r + f"{s.x:0.0f}E {s.y:0.0f}N {s.z:0.0f}Alt"
             except:
-                return r + "%s Tag Station not in dataset" % self.tag_station
+                return r + f"{self.tag_station} Tag Station not in dataset"
         if self.exact_station:
             try:
                 s = SurvexStation.objects.lookup(self.exact_station)
-                return r + "%0.0fE %0.0fN %0.0fAlt" % (s.x, s.y, s.z)
+                return r + f"{s.x:0.0f}E {s.y:0.0f}N {s.z:0.0f}Alt"
             except:
-                return r + "%s Exact Station not in dataset" % self.tag_station
+                return r + f"{self.tag_station} Exact Station not in dataset"
         if self.other_station:
             try:
                 s = SurvexStation.objects.lookup(self.other_station)
-                return r + "%0.0fE %0.0fN %0.0fAlt %s" % (s.x, s.y, s.z, self.other_description)
+                return r + f"{s.x:0.0f}E {s.y:0.0f}N {s.z:0.0f}Alt {self.other_description}"
             except:
-                return r + "%s Other Station not in dataset" % self.tag_station
+                return r + f"{self.tag_station} Other Station not in dataset"
         if self.FINDABLE_CHOICES == "S":
             r += "ERROR, Entrance has been surveyed but has no survex point"
         if self.bearings:
diff --git a/core/models/troggle.py b/core/models/troggle.py
index 947ba21..b118d78 100644
--- a/core/models/troggle.py
+++ b/core/models/troggle.py
@@ -63,7 +63,7 @@ class DataIssue(TroggleModel):
         ordering = ['date']
 
     def __str__(self):
-        return "%s - %s" % (self.parser, self.message)
+        return f"{self.parser} - {self.message}"
 
 # 
 # single Expedition, usually seen by year
@@ -90,7 +90,7 @@ class Expedition(TroggleModel):
             if len(expeditiondays) == 1:
                 return expeditiondays[0]
             else:
-                message ='! - more than one datum in an expeditionday: {}'.format(date)
+                message =f'! - more than one datum in an expeditionday: {date}'
                 DataIssue.objects.create(parser='expedition', message=message)
                 return expeditiondays[0]
         res = ExpeditionDay(expedition=self, date=date)
@@ -139,7 +139,7 @@ class Person(TroggleModel):
     
     def __str__(self):
         if self.last_name:
-            return "%s %s" % (self.first_name, self.last_name)
+            return f"{self.first_name} {self.last_name}"
         return self.first_name
 
 
@@ -205,14 +205,14 @@ class PersonExpedition(TroggleModel):
         #order_with_respect_to = 'expedition'
 
     def __str__(self):
-        return "%s: (%s)" % (self.person, self.expedition)
+        return f"{self.person}: ({self.expedition})"
     
     #why is the below a function in personexpedition, rather than in person? - AC 14 Feb 09
     def name(self):
         if self.nickname:
-            return "%s (%s) %s" % (self.person.first_name, self.nickname, self.person.last_name)
+            return f"{self.person.first_name} ({self.nickname}) {self.person.last_name}"
         if self.person.last_name:
-            return "%s %s" % (self.person.first_name, self.person.last_name)
+            return f"{self.person.first_name} {self.person.last_name}"
         return self.person.first_name
 
     def get_absolute_url(self):
diff --git a/core/templatetags/link.py b/core/templatetags/link.py
index a17dd4b..3fca805 100644
--- a/core/templatetags/link.py
+++ b/core/templatetags/link.py
@@ -5,5 +5,5 @@ register = template.Library()
 
 @register.filter()
 def link(value):
-    return mark_safe("<a href=\'%s\'>"%value.get_absolute_url()+str(value)+"</a>")
+    return mark_safe(f"<a href='{value.get_absolute_url()}'>"+str(value)+"</a>")
 
diff --git a/core/utils.py b/core/utils.py
index b2140ed..a51425c 100644
--- a/core/utils.py
+++ b/core/utils.py
@@ -141,7 +141,7 @@ def write_and_commit(files, message):
                     msgdata = 'Ask a nerd to fix this.\n\n' + cp_add.stderr + '\n\n' + cp_add.stdout  + '\n\nreturn code: ' + str(cp_add.returncode)
                     raise WriteAndCommitError(f'CANNOT git on server for this file {filename}. Edits saved but not added to git.\n\n' + msgdata)
             else:
-                print("No change %s" % filepah)
+                print(f"No change {filepah}")
         cp_commit = subprocess.run([git, "commit", "-m", message], cwd=cwd, capture_output=True, text=True)
         cp_status = subprocess.run([git, "status"], cwd=cwd, capture_output=True, text=True)
         # This produces return code = 1 if it commits OK, but when the repo still needs to be pushed to origin/expoweb
@@ -205,7 +205,7 @@ def save_carefully(objectType, lookupAttribs={}, nonLookupAttribs={}):
     except:
         print(" !! - FAIL in SAVE CAREFULLY   ===================", objectType)
         print(" !! - -- objects.get_or_create()")
-        print(" !! - lookupAttribs:{}\n !! - nonLookupAttribs:{}".format(lookupAttribs,nonLookupAttribs))
+        print(f" !! - lookupAttribs:{lookupAttribs}\n !! - nonLookupAttribs:{nonLookupAttribs}")
         raise
     if not created and not instance.new_since_parsing:
         for k, v in list(nonLookupAttribs.items()): #overwrite the existing attributes from the logbook text (except date and title)
@@ -215,12 +215,12 @@ def save_carefully(objectType, lookupAttribs={}, nonLookupAttribs={}):
         except:
             print(" !! - SAVE CAREFULLY   ===================", objectType)
             print(" !! - -- instance.save()")
-            print(" !! - lookupAttribs:{}\n !! - nonLookupAttribs:{}".format(lookupAttribs,nonLookupAttribs))
+            print(f" !! - lookupAttribs:{lookupAttribs}\n !! - nonLookupAttribs:{nonLookupAttribs}")
             raise
     try:
         msg = str(instance)
     except:
-        msg = "FAULT getting __str__ for instance with lookupattribs: {}:".format(lookupAttribs)
+        msg = f"FAULT getting __str__ for instance with lookupattribs: {lookupAttribs}:"
     if created:
         logging.info(str(instance) + ' was just added to the database for the first time. \n')
     
diff --git a/core/views/caves.py b/core/views/caves.py
index fe85949..7706315 100644
--- a/core/views/caves.py
+++ b/core/views/caves.py
@@ -155,7 +155,7 @@ def file3d(request, cave, cave_id):
             #print(" -  - Regeneration ABORT\n -  - from '{}'".format(survexpath))
             pass
         try:
-            completed_process = subprocess.run([settings.CAVERN, "--log", "--output={}".format(settings.SURVEX_DATA), "{}".format(survexpath)])
+            completed_process = subprocess.run([settings.CAVERN, "--log", f"--output={settings.SURVEX_DATA}", f"{survexpath}"])
         except OSError as ex:
             # propagate this to caller. 
             raise OSError(completed_process.stdout) from ex
@@ -164,7 +164,7 @@ def file3d(request, cave, cave_id):
         op3dlog = Path(op3d.with_suffix('.log'))
 
         if not op3d.is_file():
-            print(" -  - Regeneration FAILED\n -  - from '{}'\n -  - to   '{}'".format(survexpath, op3d))
+            print(f" -  - Regeneration FAILED\n -  - from '{survexpath}'\n -  - to   '{op3d}'")
             print(" -  - Regeneration stdout: ", completed_process.stdout)
             print(" -  - Regeneration cavern log output: ", op3dlog.read_text())
           
@@ -172,10 +172,10 @@ def file3d(request, cave, cave_id):
     def return3d(threedpath):
         if threedpath.is_file():
             response = HttpResponse(content=open(threedpath, 'rb'), content_type='application/3d')
-            response['Content-Disposition'] = 'attachment; filename={}'.format(threedpath.name)
+            response['Content-Disposition'] = f'attachment; filename={threedpath.name}'
             return response
         else:
-            message = '<h1>Path provided  does not correspond to any actual 3d file.</h1><p>path: "{}"'.format(threedpath)
+            message = f'<h1>Path provided  does not correspond to any actual 3d file.</h1><p>path: "{threedpath}"'
             #print(message)
             return HttpResponseNotFound(message) 
     
@@ -205,10 +205,10 @@ def file3d(request, cave, cave_id):
     # Get here if cave.survex_file was set but did not correspond to a valid svx file
     if survexpath.is_file():
         # a file, but invalid format
-        message='<h1>File is not valid .svx format.</h1><p>Could not generate 3d file from "{}"'.format(survexpath)
+        message=f'<h1>File is not valid .svx format.</h1><p>Could not generate 3d file from "{survexpath}"'
     else:
         # we could try to guess that 'caves-1623/' is missing,... nah.
-        message = '<h1>Path provided  does not correspond to any actual file.</h1><p>path: "{}"'.format(survexpath)
+        message = f'<h1>Path provided  does not correspond to any actual file.</h1><p>path: "{survexpath}"'
 
     return HttpResponseNotFound(message) 
     
@@ -325,9 +325,9 @@ def edit_cave(request, path = "", slug=None):
                     if a.kat_area():
                         myArea = a.kat_area()
                 if form.cleaned_data["kataster_number"]:
-                    myslug =  "%s-%s" % (myArea, form.cleaned_data["kataster_number"])
+                    myslug =  f"{myArea}-{form.cleaned_data['kataster_number']}"
                 else:
-                    myslug =  "%s-%s" % (myArea, form.cleaned_data["unofficial_number"])
+                    myslug =  f"{myArea}-{form.cleaned_data['unofficial_number']}"
             else:
                 myslug = slug
             # Converting a PENDING cave to a real cave by saving this form
@@ -345,7 +345,7 @@ def edit_cave(request, path = "", slug=None):
             try:
                 cave_file = cave.file_output()
                 print(cave_file)
-                write_and_commit([cave_file], "Online edit of %s" % cave)
+                write_and_commit([cave_file], f"Online edit of {cave}")
                 # leave other exceptions unhandled so that they bubble up to user interface
             except PermissionError:
                 message = f'CANNOT  save this file.\nPERMISSIONS incorrectly set on server for this file {cave.filename}. Ask a nerd to fix this.'
@@ -414,7 +414,7 @@ def edit_entrance(request, path = "", caveslug=None, slug=None):
                 es.save()
             entrance_file = entrance.file_output()
             cave_file = cave.file_output()
-            write_and_commit([entrance_file, cave_file], "Online edit of %s%s" % (cave, entletter))
+            write_and_commit([entrance_file, cave_file], f"Online edit of {cave}{entletter}")
             entrance.save()
             if slug is None:
                 entrance_letter.save()
diff --git a/core/views/editor_helpers.py b/core/views/editor_helpers.py
index 1988351..d7fd05f 100644
--- a/core/views/editor_helpers.py
+++ b/core/views/editor_helpers.py
@@ -39,13 +39,13 @@ def image_selector(request, path):
                     base = f"{directory}/"
                 else:
                     base = ""
-                thumbnail_url = reverse('expopage', args=["%st/%s" % (base, f.name)])
+                thumbnail_url = reverse('expopage', args=[f"{base}t/{f.name}"])
                 name_base = f.name.rsplit('.', 1)[0]
                 page_path_base = Path(settings.EXPOWEB) / directory / "l"
-                if ((page_path_base / ("%s.htm" % name_base)).is_file()):
-                    page_url = reverse('expopage', args=["%sl/%s.htm" % (base, name_base)])
+                if ((page_path_base / (f"{name_base}.htm")).is_file()):
+                    page_url = reverse('expopage', args=[f"{base}l/{name_base}.htm"])
                 else:
-                    page_url = reverse('expopage', args=["%s/l/%s.html" % (base, name_base)])
+                    page_url = reverse('expopage', args=[f"{base}/l/{name_base}.html"])
             
                 thumbnails.append({"thumbnail_url": thumbnail_url, "page_url": page_url})
     
@@ -128,7 +128,7 @@ class NewWebImageForm(forms.Form):
     def clean_file_(self):
         for rel_path, full_path in zip(self.get_rel_paths(), self.get_full_paths()):
             if full_path.exists():
-                raise forms.ValidationError("File already exists in %s" % rel_path)
+                raise forms.ValidationError(f"File already exists in {rel_path}")
         return self.cleaned_data['file_']
         
 class HTMLarea(forms.Textarea):
diff --git a/core/views/expo.py b/core/views/expo.py
index 021415f..c443c38 100644
--- a/core/views/expo.py
+++ b/core/views/expo.py
@@ -219,7 +219,7 @@ def expopage(request, path):
     #print(" - EXPOPAGES delivering the file: '{}':{} as MIME type: {}".format(request.path, path,getmimetype(path)),flush=True)
 
     if path.startswith("noinfo") and settings.PUBLIC_SITE and not request.user.is_authenticated:
-        return HttpResponseRedirect(urljoin(reverse("auth_login"),'?next={}'.format(request.path)))
+        return HttpResponseRedirect(urljoin(reverse("auth_login"),f'?next={request.path}'))
 
     if path.startswith("admin/"):
         # don't even attempt to handle these sorts of mistakes
@@ -354,7 +354,7 @@ def editexpopage(request, path):
                 postbody = "</html>\n" 
             body = pageform.cleaned_data["html"]
             body = body.replace("\r", "")
-            result = "%s<head%s>%s</head>%s<body%s>\n%s</body>%s" % (preheader, headerargs, head, postheader, bodyargs, body, postbody)
+            result = f"{preheader}<head{headerargs}>{head}</head>{postheader}<body{bodyargs}>\n{body}</body>{postbody}"
             
             if not filefound or result != html: # Check if content changed at all
                 try:
diff --git a/core/views/logbooks.py b/core/views/logbooks.py
index 9c3d8c5..517a48b 100644
--- a/core/views/logbooks.py
+++ b/core/views/logbooks.py
@@ -238,4 +238,4 @@ def get_people(request, expeditionslug):
 
 def get_logbook_entries(request, expeditionslug):
     exp = Expedition.objects.get(year = expeditionslug)
-    return render(request,'options.html', {"items": [(le.slug, "%s - %s" % (le.date, le.title)) for le in exp.logbookentry_set.all()]})
+    return render(request,'options.html', {"items": [(le.slug, f"{le.date} - {le.title}") for le in exp.logbookentry_set.all()]})
diff --git a/core/views/statistics.py b/core/views/statistics.py
index c22d1a4..34fe66c 100644
--- a/core/views/statistics.py
+++ b/core/views/statistics.py
@@ -125,10 +125,10 @@ def pathsreport(request):
 
 def stats(request):
     statsDict={}
-    statsDict['expoCount'] = "{:,}".format(Expedition.objects.count())
-    statsDict['caveCount'] = "{:,}".format(Cave.objects.count())
-    statsDict['personCount'] = "{:,}".format(Person.objects.count())
-    statsDict['logbookEntryCount'] = "{:,}".format(LogbookEntry.objects.count())
+    statsDict['expoCount'] = f"{Expedition.objects.count():,}"
+    statsDict['caveCount'] = f"{Cave.objects.count():,}"
+    statsDict['personCount'] = f"{Person.objects.count():,}"
+    statsDict['logbookEntryCount'] = f"{LogbookEntry.objects.count():,}"
 
     legsbyexpo = [ ]
     addupsurvexlength = 0
@@ -142,8 +142,8 @@ def stats(request):
             legsyear += int(survexblock.legsall)
         addupsurvexlength += survexleglength
         addupsurvexlegs += legsyear
-        legsbyexpo.append((expedition, {"nsurvexlegs": "{:,}".format(legsyear), 
-                "survexleglength":"{:,.0f}".format(survexleglength)}))
+        legsbyexpo.append((expedition, {"nsurvexlegs": f"{legsyear:,}", 
+                "survexleglength":f"{survexleglength:,.0f}"}))
     legsbyexpo.reverse() 
 
     renderDict = {**statsDict, **{ "addupsurvexlength":addupsurvexlength/1000, "legsbyexpo":legsbyexpo, "nsurvexlegs":addupsurvexlegs }} # new syntax
diff --git a/databaseReset.py b/databaseReset.py
index 0ab5cf1..630d3c6 100644
--- a/databaseReset.py
+++ b/databaseReset.py
@@ -26,13 +26,13 @@ print(" - settings on loading databaseReset.py")
 
 import django
 
-print(" - Memory footprint before loading Django: {:.3f} MB".format(resource.getrusage(resource.RUSAGE_SELF)[2]/1024.0))
+print(f" - Memory footprint before loading Django: {resource.getrusage(resource.RUSAGE_SELF)[2] / 1024.0:.3f} MB")
 try:
     django.setup()
 except:
     print(" ! Cyclic reference failure. Can occur when the initial db is empty. Fixed now (in UploadFileForm) but easy to reintroduce..")
     raise
-print(" - Memory footprint after loading Django: {:.3f} MB".format(resource.getrusage(resource.RUSAGE_SELF)[2]/1024.0))
+print(f" - Memory footprint after loading Django: {resource.getrusage(resource.RUSAGE_SELF)[2] / 1024.0:.3f} MB")
 
 from troggle.core.models.troggle import DataIssue
 import troggle.core.models.survex
@@ -93,10 +93,10 @@ def reinit_db():
         # this is now completely failing to nuke MariaDB adequately, and it crashes when creating Area objects with a no null parent message
         # when null parents are explciitly allowed in the model.
         cursor = django.db.connection.cursor()
-        cursor.execute("DROP DATABASE %s" % currentdbname)
-        cursor.execute("CREATE DATABASE %s" % currentdbname)
-        cursor.execute("ALTER DATABASE %s CHARACTER SET=utf8" % currentdbname)
-        cursor.execute("USE %s" % currentdbname)
+        cursor.execute(f"DROP DATABASE {currentdbname}")
+        cursor.execute(f"CREATE DATABASE {currentdbname}")
+        cursor.execute(f"ALTER DATABASE {currentdbname} CHARACTER SET=utf8")
+        cursor.execute(f"USE {currentdbname}")
         print(f" - Nuked : {currentdbname}\n")
 
     print(" - Migrating: " + django.db.connections.databases['default']['NAME'])
@@ -117,7 +117,7 @@ def reinit_db():
     with transaction.atomic():
         try:
             print(" - Setting up expo user on: " + django.db.connections.databases['default']['NAME'])
-            print(" - user: {} ({:.5}...) <{}> ".format(expouser, expouserpass, expouseremail))
+            print(f" - user: {expouser} ({expouserpass:.5}...) <{expouseremail}> ")
             user = User.objects.create_user(expouser, expouseremail, expouserpass)
             user.is_staff = False
             user.is_superuser = False
@@ -136,7 +136,7 @@ def reinit_db():
     with transaction.atomic():
         try:
             print(" - Setting up expoadmin user on: " + django.db.connections.databases['default']['NAME'])
-            print(" - user: {} ({:.5}...) <{}> ".format(expoadminuser, expoadminuserpass, expoadminuseremail))
+            print(f" - user: {expoadminuser} ({expoadminuserpass:.5}...) <{expoadminuseremail}> ")
             user = User.objects.create_user(expoadminuser, expoadminuseremail, expoadminuserpass)
             user.is_staff = True
             user.is_superuser = True
@@ -157,7 +157,7 @@ def memdumpsql(fn):
     from dump import _iterdump
     with open(fn, 'w') as f:
         for line in _iterdump(djconn):
-            f.write('%s\n' % line.encode("utf8"))
+            f.write(f"{line.encode('utf8')}\n")
     return True
 
 # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
@@ -195,7 +195,7 @@ class JobQueue():
                 for j in data:
                     self.results[j] = data[j]
             except:
-                print("FAILURE parsing JSON file %s" % (self.tfile))
+                print(f"FAILURE parsing JSON file {self.tfile}")
                 # Python bug: https://github.com/ShinNoNoir/twitterwebsearch/issues/12
             f.close()
         for j in self.results_order:
@@ -229,7 +229,7 @@ class JobQueue():
         print("** Running job ", self.runlabel,end=" to ")
         print(django.db.connections.databases['default']['NAME'])
         jobstart = time.time()
-        print("-- Initial memory in use {:.3f} MB".format(get_process_memory()))
+        print(f"-- Initial memory in use {get_process_memory():.3f} MB")
         self.results["date"].pop()
         self.results["date"].append(jobstart)
         self.results["runlabel"].pop()
@@ -244,14 +244,14 @@ class JobQueue():
             memend = get_process_memory()
             duration = time.time()-start
             #print(" - MEMORY start:{:.3f} MB end:{:.3f} MB change={:.3f} MB".format(memstart,memend, ))
-            print("\n*- Ended \"",  runfunction[0], "\"  {:.1f} seconds + {:.3f} MB ({:.3f} MB)".format(duration, memend-memstart, memend))
+            print("\n*- Ended \"",  runfunction[0], f"\"  {duration:.1f} seconds + {memend - memstart:.3f} MB ({memend:.3f} MB)")
             self.results[runfunction[0]].pop()  # the null item
             self.results[runfunction[0]].append(duration)
                
 
         jobend = time.time()
         jobduration = jobend-jobstart
-        print("** Ended job   %s  -  %.1f seconds total." % (self.runlabel,jobduration))
+        print(f"** Ended job   {self.runlabel}  -  {jobduration:.1f} seconds total.")
         return True
 
 
@@ -310,13 +310,13 @@ class JobQueue():
                             else:
                                 s = 0
                             days = (s)/(24*60*60)
-                            print('%8.2f' % days, end=' ')
+                            print(f'{days:8.2f}', end=' ')
                 elif r[i]: 
-                    print('%8.1f' % r[i], end=' ')
+                    print(f'{r[i]:8.1f}', end=' ')
                     if i == len(r)-1 and r[i-1]:
                         percen = 100* (r[i] - r[i-1])/r[i-1]
                         if abs(percen) >0.1:
-                            print('%8.1f%%' % percen, end=' ')
+                            print(f'{percen:8.1f}%', end=' ')
                 else:
                     print("      - ", end=' ')
             print("")
@@ -441,7 +441,7 @@ if __name__ == "__main__":
         exit()
     else:
         usage()
-        print("%s not recognised as a command." % sys.argv[1])
+        print(f"{sys.argv[1]} not recognised as a command.")
         exit()
 
     jq.run()
diff --git a/dump.py b/dump.py
index 4464823..4b8c395 100644
--- a/dump.py
+++ b/dump.py
@@ -46,11 +46,11 @@ def _iterdump(connection):
         #        qtable,
         #        sql.replace("''")))
         else:
-            yield('{0};'.format(sql))
+            yield(f'{sql};')
 
         # Build the insert statement for each row of the current table
         table_name_ident = table_name.replace('"', '""')
-        res = cu.execute('PRAGMA table_info("{0}")'.format(table_name_ident))
+        res = cu.execute(f'PRAGMA table_info("{table_name_ident}")')
         column_names = [str(table_info[1]) for table_info in res.fetchall()]
         q = """SELECT 'INSERT INTO "{0}" VALUES({1})' FROM "{0}";""".format(
             table_name_ident,
@@ -68,6 +68,6 @@ def _iterdump(connection):
         """
     schema_res = cu.execute(q)
     for name, type, sql in schema_res.fetchall():
-        yield('{0};'.format(sql))
+        yield(f'{sql};')
 
     yield('COMMIT;')
\ No newline at end of file
diff --git a/modelviz.py b/modelviz.py
index 2603fca..22919ca 100644
--- a/modelviz.py
+++ b/modelviz.py
@@ -116,7 +116,7 @@ def generate_dot(app_labels, **kwargs):
     for app_label in app_labels:
         app = models.get_app(app_label)
         graph = Context({
-            'name': '"%s"' % app.__name__,
+            'name': f'"{app.__name__}"',
             'disable_fields': disable_fields,
             'models': []
             })
diff --git a/reset-django.py b/reset-django.py
index 92af453..893aee1 100644
--- a/reset-django.py
+++ b/reset-django.py
@@ -62,14 +62,14 @@ def delete_sqlite3():
     if os.path.exists(db_file):
         try:
             os.remove(db_file)
-            print("\n>>> troggle.sqlite: {} DELETED\n".format(db_file))
+            print(f"\n>>> troggle.sqlite: {db_file} DELETED\n")
         except:
-            print("troggle.sqlite: {} NOT deleted".format(db_file))
+            print(f"troggle.sqlite: {db_file} NOT deleted")
 
 
 def main():
     global folders
-    print("base directory used: {}".format(base_dir))
+    print(f"base directory used: {base_dir}")
 
 
     try: