diff --git a/imgsrc/srv/generate.py b/imgsrc/srv/generate.py
index 93c2cf9c2d..c5506ca2ed 100644
--- a/imgsrc/srv/generate.py
+++ b/imgsrc/srv/generate.py
@@ -42,7 +42,7 @@ def merge():
                 recover=True, no_network=True, resolve_entities=False
             )
         )
-        symbol = ans.makeelement('{{{}}}symbol'.format(SVG_NS))
+        symbol = ans.makeelement('{%s}symbol' % SVG_NS)  # noqa: UP031
         symbol.set('viewBox', svg.get('viewBox'))
         symbol.set('id', 'icon-' + f.rpartition('.')[0])
         for child in svg.iterchildren('*'):
diff --git a/manual/conf.py b/manual/conf.py
index bf9a699f04..e41fd87dbc 100644
--- a/manual/conf.py
+++ b/manual/conf.py
@@ -253,5 +253,5 @@ latex_show_pagerefs = True
 latex_show_urls = 'footnote'
 latex_elements = {
     'papersize':'letterpaper',
-    'preamble': r'\renewcommand{{\pageautorefname}}{{{}}}'.format(_('page')),
+    'preamble': r'\renewcommand{\pageautorefname}{%s}' % _('page'),  # noqa: UP031
 }
diff --git a/recipes/liberation.recipe b/recipes/liberation.recipe
index 531b02a41f..18b936ac6a 100644
--- a/recipes/liberation.recipe
+++ b/recipes/liberation.recipe
@@ -136,7 +136,7 @@ class Liberation(BasicNewsRecipe):
         b64 = base64.b64decode(self.key)
         query = {
             'website': 'liberation',
-            'website_url': '{}'.format(slug),
+            'website_url': str(slug),
             'published': 'true',
             '_sourceInclude': '_id,content_restrictions.content_code,credits,promo_items.basic.caption,promo_items.basic.credits,promo_items.basic.url,promo_items.basic.height,promo_items.basic.width,promo_items.basic.resized_image_urls,promo_items.basic.last_updated_date,promo_items.lead_art.caption,promo_items.lead_art.credits,promo_items.lead_art.url,promo_items.lead_art.height,promo_items.lead_art.width,promo_items.lead_art.resized_image_urls,promo_items.lead_art.last_updated_date,source.additional_properties.legacy_url,content_elements,source.source_id,taxonomy.primary_section.additional_properties.original._admin.alias_ids,taxonomy.primary_section.additional_properties.original.navigation.nav_title,taxonomy.primary_section._id,taxonomy.primary_section.name,taxonomy.primary_section.path,taxonomy.tags,label,subheadlines.basic,headlines.basic,source.additional_properties.legacy_url,source.source_type,first_publish_date,display_date,canonical_url'  # noqa: E501
         }
diff --git a/setup/__init__.py b/setup/__init__.py
index 1886deafc1..d43f1e8dd4 100644
--- a/setup/__init__.py
+++ b/setup/__init__.py
@@ -126,7 +126,7 @@ def initialize_constants():
     with open(os.path.join(SRC, 'calibre/constants.py'), 'rb') as f:
         src = f.read().decode('utf-8')
     nv = re.search(r'numeric_version\s+=\s+\((\d+), (\d+), (\d+)\)', src)
-    __version__ = '{}.{}.{}'.format(nv.group(1), nv.group(2), nv.group(3))
+    __version__ = '.'.join([nv.group(1), nv.group(2), nv.group(3)])
     __appname__ = re.search(r'__appname__\s+=\s+(u{0,1})[\'"]([^\'"]+)[\'"]',
             src).group(2)
     with open(os.path.join(SRC, 'calibre/linux.py'), 'rb') as sf:
diff --git a/setup/git_pre_commit_hook.py b/setup/git_pre_commit_hook.py
index 62be70ec45..afe837d1c6 100755
--- a/setup/git_pre_commit_hook.py
+++ b/setup/git_pre_commit_hook.py
@@ -23,8 +23,8 @@ message with the summary of the closed bug.
 
 
 LAUNCHPAD = os.path.expanduser('~/work/env/launchpad.py')
-LAUNCHPAD_BUG = 'https://bugs.launchpad.net/calibre/+bug/%s'
-GITHUB_BUG = 'https://api.github.com/repos/kovidgoyal/calibre/issues/%s'
+LAUNCHPAD_BUG = 'https://bugs.launchpad.net/calibre/+bug/{}'
+GITHUB_BUG = 'https://api.github.com/repos/kovidgoyal/calibre/issues/{}'
 BUG_PAT = r'(Fix|Implement|Fixes|Fixed|Implemented|See)\s+#(\d+)'
 
 socket.setdefaulttimeout(90)
@@ -44,18 +44,18 @@ class Bug:
 
         if int(bug) > 100000:  # Launchpad bug
             try:
-                raw = urllib.request.urlopen(LAUNCHPAD_BUG % bug).read()
+                raw = urllib.request.urlopen(LAUNCHPAD_BUG.format(bug)).read()
                 h1 = html.fromstring(raw).xpath('//h1[@id="edit-title"]')[0]
                 summary = html.tostring(h1, method='text', encoding=str).strip()
             except:
                 summary = 'Private bug'
         else:
-            summary = json.loads(urllib.request.urlopen(GITHUB_BUG % bug).read())['title']
+            summary = json.loads(urllib.request.urlopen(GITHUB_BUG.format(bug)).read())['title']
         if summary:
             print('Working on bug:', summary)
             if int(bug) > 100000 and action != 'See':
                 self.close_bug(bug, action)
-                return match.group() + f' [{summary}]({LAUNCHPAD_BUG % bug})'
+                return match.group() + f' [{summary}]({LAUNCHPAD_BUG.format(bug)})'
             return match.group() + ' ({})'.format(summary)
         return match.group()
 
diff --git a/setup/hosting.py b/setup/hosting.py
index 5415fe11ba..ff3675d30a 100644
--- a/setup/hosting.py
+++ b/setup/hosting.py
@@ -416,20 +416,20 @@ def upload_to_servers(files, version):  # {{{
 
     # for server, rdir in {'files':'/srv/download/'}.items():
     #     print('Uploading to server:', server)
-    #     server = '%s.calibre-ebook.com' % server
+    #     server = f'{server}.calibre-ebook.com'
     #     # Copy the generated index files
     #     print('Copying generated index')
     #     check_call(['rsync', '-hza', '-e', 'ssh -x', '--include', '*.html',
-    #                 '--filter', '-! */', base, 'root@%s:%s' % (server, rdir)])
+    #                 '--filter', '-! */', base, f'root@{server}:{rdir}'])
     #     # Copy the release files
-    #     rdir = '%s%s/' % (rdir, version)
+    #     rdir = f'{rdir}{version}/'
     #     for x in files:
     #         start = time.time()
     #         print('Uploading', x)
     #         for i in range(5):
     #             try:
     #                 check_call(['rsync', '-h', '-z', '--progress', '-e', 'ssh -x', x,
-    #                 'root@%s:%s'%(server, rdir)])
+    #                 f'root@{server}:{rdir}'])
     #             except KeyboardInterrupt:
     #                 raise SystemExit(1)
     #             except:
diff --git a/setup/plugins_mirror.py b/setup/plugins_mirror.py
index fe381f9dee..3ee2f058ca 100644
--- a/setup/plugins_mirror.py
+++ b/setup/plugins_mirror.py
@@ -502,25 +502,25 @@ def create_index(index, raw_stats):
 <head><meta charset="utf-8"><title>Index of calibre plugins</title>
 <link rel="icon" type="image/x-icon" href="//calibre-ebook.com/favicon.ico" />
 <style type="text/css">
-body {{ background-color: #eee; }}
-a {{ text-decoration: none }}
-a:hover, h3:hover {{ color: red }}
-a:visited {{ color: blue }}
-ul {{ list-style-type: none; font-size: smaller }}
-li {{ display: inline }}
-li+li:before {{ content: " - " }}
-.end {{ border-bottom: solid 1pt black; padding-bottom: 0.5ex; margin-bottom: 4ex; }}
-h1 img, h3 img {{ vertical-align: middle; margin-right: 0.5em; }}
-h1 {{ text-align: center }}
-.download-count {{ color: gray; font-size: smaller }}
+body { background-color: #eee; }
+a { text-decoration: none }
+a:hover, h3:hover { color: red }
+a:visited { color: blue }
+ul { list-style-type: none; font-size: smaller }
+li { display: inline }
+li+li:before { content: " - " }
+.end { border-bottom: solid 1pt black; padding-bottom: 0.5ex; margin-bottom: 4ex; }
+h1 img, h3 img { vertical-align: middle; margin-right: 0.5em; }
+h1 { text-align: center }
+.download-count { color: gray; font-size: smaller }
 </style>
 </head>
 <body>
 <h1><img src="//manual.calibre-ebook.com/_static/logo.png">Index of calibre plugins</h1>
 <div style="text-align:center"><a href="stats.html">Download counts for all plugins</a></div>
-{}
+%s
 </body>
-</html>'''.format('\n'.join(plugins))
+</html>''' % ('\n'.join(plugins))  # noqa: UP031
     raw = index.encode('utf-8')
     try:
         with open('index.html', 'rb') as f:
@@ -541,20 +541,20 @@ h1 {{ text-align: center }}
 <head><meta charset="utf-8"><title>Stats for calibre plugins</title>
 <link rel="icon" type="image/x-icon" href="//calibre-ebook.com/favicon.ico" />
 <style type="text/css">
-body {{ background-color: #eee; }}
-h1 img, h3 img {{ vertical-align: middle; margin-right: 0.5em; }}
-h1 {{ text-align: center }}
+body { background-color: #eee; }
+h1 img, h3 img { vertical-align: middle; margin-right: 0.5em; }
+h1 { text-align: center }
 </style>
 </head>
 <body>
 <h1><img src="//manual.calibre-ebook.com/_static/logo.png">Stats for calibre plugins</h1>
 <table>
 <tr><th>Plugin</th><th>Total downloads</th></tr>
-{}
+%s
 </table>
 </body>
 </html>
-    '''.format('\n'.join(pstats))
+    ''' % ('\n'.join(pstats))  # noqa: UP031
     raw = stats.encode('utf-8')
     try:
         with open('stats.html', 'rb') as f:
diff --git a/setup/translations.py b/setup/translations.py
index 7c0640513e..b375abcab4 100644
--- a/setup/translations.py
+++ b/setup/translations.py
@@ -171,14 +171,14 @@ class POT(Command):  # {{{
     def pot_header(self, appname=__appname__, version=__version__):
         return textwrap.dedent('''\
         # Translation template file..
-        # Copyright (C) %(year)s Kovid Goyal
-        # Kovid Goyal <kovid@kovidgoyal.net>, %(year)s.
+        # Copyright (C) {year} Kovid Goyal
+        # Kovid Goyal <kovid@kovidgoyal.net>, {year}.
         #
         msgid ""
         msgstr ""
-        "Project-Id-Version: %(appname)s %(version)s\\n"
-        "POT-Creation-Date: %(time)s\\n"
-        "PO-Revision-Date: %(time)s\\n"
+        "Project-Id-Version: {appname} {version}\\n"
+        "POT-Creation-Date: {time}\\n"
+        "PO-Revision-Date: {time}\\n"
         "Last-Translator: Automatically generated\\n"
         "Language-Team: LANGUAGE\\n"
         "MIME-Version: 1.0\\n"
@@ -187,7 +187,7 @@ class POT(Command):  # {{{
         "Content-Type: text/plain; charset=UTF-8\\n"
         "Content-Transfer-Encoding: 8bit\\n"
 
-        ''')%dict(appname=appname, version=version,
+        ''').format(appname=appname, version=version,
                 year=time.strftime('%Y'),
                 time=time.strftime('%Y-%m-%d %H:%M+%Z'))
 
diff --git a/src/odf/attrconverters.py b/src/odf/attrconverters.py
index a17117369f..cb31accb94 100644
--- a/src/odf/attrconverters.py
+++ b/src/odf/attrconverters.py
@@ -126,7 +126,7 @@ def __save_prefix(attribute, arg, element):
         return str(arg)
     namespace = element.get_knownns(prefix)
     if namespace is None:
-        # raise ValueError("'%s' is an unknown prefix" % unicode_type(prefix))
+        # raise ValueError(f"'{unicode_type(prefix)}' is an unknown prefix")
         return str(arg)
     return str(arg)
 
diff --git a/src/odf/odf2xhtml.py b/src/odf/odf2xhtml.py
index 60f80d2b5e..1ab829eb67 100644
--- a/src/odf/odf2xhtml.py
+++ b/src/odf/odf2xhtml.py
@@ -662,7 +662,7 @@ class ODF2XHTML(handler.ContentHandler):
         ''' Get the title from the meta data and create a HTML <title>
         '''
         self.title = ''.join(self.data)
-        # self.metatags.append('<title>%s</title>\n' % escape(self.title))
+        # self.metatags.append('<title>{}</title>\n'.format(escape(self.title)))
         self.data = []
 
     def e_dc_metatag(self, tag, attrs):
@@ -1355,7 +1355,7 @@ dl.notes dd:last-of-type { page-break-after: avoid }
             attrs = {'start': unicode_type(self.list_number_map[number_class])}
         if self.generate_css:
             attrs['class'] = list_class
-        self.opentag('{}'.format(tag_name), attrs)
+        self.opentag(str(tag_name), attrs)
         self.purgedata()
 
     def e_text_list(self, tag, attrs):
diff --git a/src/odf/opendocument.py b/src/odf/opendocument.py
index 7689960f6b..2695646772 100644
--- a/src/odf/opendocument.py
+++ b/src/odf/opendocument.py
@@ -403,7 +403,7 @@ class OpenDocument:
                 self._z.writestr(zi, fileobj)
         # According to section 17.7.3 in ODF 1.1, the pictures folder should not have a manifest entry
 #       if hasPictures:
-#           self.manifest.addElement(manifest.FileEntry(fullpath="%sPictures/" % folder, mediatype=""))
+#           self.manifest.addElement(manifest.FileEntry(fullpath=f"{folder}Pictures/", mediatype=""))
         # Look in subobjects
         subobjectnum = 1
         for subobject in object.childobjects: