diff --git a/django/contrib/admin/helpers.py b/django/contrib/admin/helpers.py
index 27b35f6ce8..b038b3ebbb 100644
--- a/django/contrib/admin/helpers.py
+++ b/django/contrib/admin/helpers.py
@@ -95,7 +95,7 @@ class AdminForm:
     def media(self):
         media = self.form.media
         for fs in self:
-            media = media + fs.media
+            media += fs.media
         return media
 
 
@@ -456,7 +456,7 @@ class InlineAdminFormSet:
     def media(self):
         media = self.opts.media + self.formset.media
         for fs in self:
-            media = media + fs.media
+            media += fs.media
         return media
 
 
diff --git a/django/contrib/admin/options.py b/django/contrib/admin/options.py
index 215df9a059..e6d4ae12bb 100644
--- a/django/contrib/admin/options.py
+++ b/django/contrib/admin/options.py
@@ -1840,7 +1840,7 @@ class ModelAdmin(BaseModelAdmin):
             request, formsets, inline_instances, obj
         )
         for inline_formset in inline_formsets:
-            media = media + inline_formset.media
+            media += inline_formset.media
 
         if add:
             title = _("Add %s")
diff --git a/django/contrib/admin/static/admin/js/core.js b/django/contrib/admin/static/admin/js/core.js
index afdae281c3..0344a13f42 100644
--- a/django/contrib/admin/static/admin/js/core.js
+++ b/django/contrib/admin/static/admin/js/core.js
@@ -119,11 +119,11 @@ function findPosY(obj) {
         let result = '', i = 0;
         while (i < format.length) {
             if (format.charAt(i) === '%') {
-                result = result + fields[format.charAt(i + 1)];
+                result += fields[format.charAt(i + 1)];
                 ++i;
             }
             else {
-                result = result + format.charAt(i);
+                result += format.charAt(i);
             }
             ++i;
         }
diff --git a/django/contrib/auth/migrations/0011_update_proxy_permissions.py b/django/contrib/auth/migrations/0011_update_proxy_permissions.py
index b792141d59..aa6ddd50c5 100644
--- a/django/contrib/auth/migrations/0011_update_proxy_permissions.py
+++ b/django/contrib/auth/migrations/0011_update_proxy_permissions.py
@@ -32,7 +32,7 @@ def update_proxy_model_permissions(apps, schema_editor, reverse=False):
         ]
         permissions_query = Q(codename__in=proxy_default_permissions_codenames)
         for codename, name in opts.permissions:
-            permissions_query = permissions_query | Q(codename=codename, name=name)
+            permissions_query |= Q(codename=codename, name=name)
         content_type_manager = ContentType.objects.db_manager(alias)
         concrete_content_type = content_type_manager.get_for_model(
             Model, for_concrete_model=True
diff --git a/django/db/backends/base/schema.py b/django/db/backends/base/schema.py
index bf2476a63e..fe31967ce2 100644
--- a/django/db/backends/base/schema.py
+++ b/django/db/backends/base/schema.py
@@ -997,7 +997,7 @@ class BaseDatabaseSchemaEditor:
             if not four_way_default_alteration:
                 # If we don't have to do a 4-way default alteration we can
                 # directly run a (NOT) NULL alteration
-                actions = actions + null_actions
+                actions += null_actions
             # Combine actions together if we can (e.g. postgres)
             if self.connection.features.supports_combined_alters and actions:
                 sql, params = tuple(zip(*actions))
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index 2ccd3bc028..29e43d1f62 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -528,7 +528,7 @@ class FormatStylePlaceholderCursor:
         elif hasattr(params, "keys"):
             # Handle params as dict
             args = {k: ":%s" % k for k in params}
-            query = query % args
+            query %= args
         elif unify_by_values and params:
             # Handle params as a dict with unified query parameters by their
             # values. It can be used only in single query execute() because
@@ -542,11 +542,11 @@ class FormatStylePlaceholderCursor:
             }
             args = [params_dict[param] for param in params]
             params = {value: key for key, value in params_dict.items()}
-            query = query % tuple(args)
+            query %= tuple(args)
         else:
             # Handle params as sequence
             args = [(":arg%d" % i) for i in range(len(params))]
-            query = query % tuple(args)
+            query %= tuple(args)
         return query, self._format_params(params)
 
     def execute(self, query, params=None):
diff --git a/django/db/backends/oracle/introspection.py b/django/db/backends/oracle/introspection.py
index ce743b291d..363b83efca 100644
--- a/django/db/backends/oracle/introspection.py
+++ b/django/db/backends/oracle/introspection.py
@@ -166,7 +166,7 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
         for desc in cursor.description:
             name = desc[0]
             internal_size, default, collation, is_autofield, is_json = field_map[name]
-            name = name % {}  # cx_Oracle, for some reason, doubles percent signs.
+            name %= {}  # cx_Oracle, for some reason, doubles percent signs.
             description.append(
                 FieldInfo(
                     self.identifier_converter(name),
diff --git a/django/db/backends/sqlite3/_functions.py b/django/db/backends/sqlite3/_functions.py
index 49bd98cc5a..b590111ec5 100644
--- a/django/db/backends/sqlite3/_functions.py
+++ b/django/db/backends/sqlite3/_functions.py
@@ -134,7 +134,7 @@ def _sqlite_date_trunc(lookup_type, dt, tzname, conn_tzname):
     elif lookup_type == "month":
         return f"{dt.year:04d}-{dt.month:02d}-01"
     elif lookup_type == "week":
-        dt = dt - timedelta(days=dt.weekday())
+        dt -= timedelta(days=dt.weekday())
         return f"{dt.year:04d}-{dt.month:02d}-{dt.day:02d}"
     elif lookup_type == "day":
         return f"{dt.year:04d}-{dt.month:02d}-{dt.day:02d}"
@@ -205,7 +205,7 @@ def _sqlite_datetime_trunc(lookup_type, dt, tzname, conn_tzname):
     elif lookup_type == "month":
         return f"{dt.year:04d}-{dt.month:02d}-01 00:00:00"
     elif lookup_type == "week":
-        dt = dt - timedelta(days=dt.weekday())
+        dt -= timedelta(days=dt.weekday())
         return f"{dt.year:04d}-{dt.month:02d}-{dt.day:02d} 00:00:00"
     elif lookup_type == "day":
         return f"{dt.year:04d}-{dt.month:02d}-{dt.day:02d} 00:00:00"
diff --git a/django/db/models/fields/json.py b/django/db/models/fields/json.py
index 7296fe42bc..22c7e2ad00 100644
--- a/django/db/models/fields/json.py
+++ b/django/db/models/fields/json.py
@@ -292,7 +292,7 @@ class JSONExact(lookups.Exact):
             rhs_params = ["null"]
         if connection.vendor == "mysql":
             func = ["JSON_EXTRACT(%s, '$')"] * len(rhs_params)
-            rhs = rhs % tuple(func)
+            rhs %= tuple(func)
         return rhs, rhs_params
 
 
@@ -455,9 +455,9 @@ class KeyTransformIn(lookups.In):
                 value = json.loads(param)
                 sql = "%s(JSON_OBJECT('value' VALUE %%s FORMAT JSON), '$.value')"
                 if isinstance(value, (list, dict)):
-                    sql = sql % "JSON_QUERY"
+                    sql %= "JSON_QUERY"
                 else:
-                    sql = sql % "JSON_VALUE"
+                    sql %= "JSON_VALUE"
             elif connection.vendor == "mysql" or (
                 connection.vendor == "sqlite"
                 and params[0] not in connection.ops.jsonfield_datatype_values
@@ -482,7 +482,7 @@ class KeyTransformExact(JSONExact):
                     func.append(sql % "JSON_QUERY")
                 else:
                     func.append(sql % "JSON_VALUE")
-            rhs = rhs % tuple(func)
+            rhs %= tuple(func)
         elif connection.vendor == "sqlite":
             func = []
             for value in rhs_params:
@@ -490,7 +490,7 @@ class KeyTransformExact(JSONExact):
                     func.append("%s")
                 else:
                     func.append("JSON_EXTRACT(%s, '$')")
-            rhs = rhs % tuple(func)
+            rhs %= tuple(func)
         return rhs, rhs_params
 
     def as_oracle(self, compiler, connection):
diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py
index 63ed2ff4c7..c763f555e3 100644
--- a/django/db/models/fields/related.py
+++ b/django/db/models/fields/related.py
@@ -355,7 +355,7 @@ class RelatedField(FieldCacheMixin, Field):
             else:
                 related_name = self.opts.default_related_name
             if related_name:
-                related_name = related_name % {
+                related_name %= {
                     "class": cls.__name__.lower(),
                     "model_name": cls._meta.model_name.lower(),
                     "app_label": cls._meta.app_label.lower(),
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py
index 318e6b8707..f3b2b3da41 100644
--- a/django/db/models/sql/compiler.py
+++ b/django/db/models/sql/compiler.py
@@ -2046,7 +2046,7 @@ class SQLAggregateCompiler(SQLCompiler):
             elide_empty=self.elide_empty,
         ).as_sql(with_col_aliases=True)
         sql = "SELECT %s FROM (%s) subquery" % (sql, inner_query_sql)
-        params = params + inner_query_params
+        params += inner_query_params
         return sql, params
 
 
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index c2a71ff589..9735ce10c8 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -1531,7 +1531,7 @@ class Query(BaseExpression):
     ):
         """Add a Q-object to the current filter."""
         connector = q_object.connector
-        current_negated = current_negated ^ q_object.negated
+        current_negated ^= q_object.negated
         branch_negated = branch_negated or q_object.negated
         target_clause = WhereNode(connector=connector, negated=q_object.negated)
         joinpromoter = JoinPromoter(
diff --git a/django/forms/forms.py b/django/forms/forms.py
index 35471345c9..7c9f1034d2 100644
--- a/django/forms/forms.py
+++ b/django/forms/forms.py
@@ -492,7 +492,7 @@ class BaseForm(RenderableFormMixin):
         """Return all media required to render the widgets on this form."""
         media = Media()
         for field in self.fields.values():
-            media = media + field.widget.media
+            media += field.widget.media
         return media
 
     def is_multipart(self):
diff --git a/django/forms/models.py b/django/forms/models.py
index 89cb000271..b79157ce68 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -316,7 +316,7 @@ class ModelFormMetaclass(DeclarativeFieldsMetaclass):
             missing_fields = none_model_fields.difference(new_class.declared_fields)
             if missing_fields:
                 message = "Unknown field(s) (%s) specified for %s"
-                message = message % (", ".join(missing_fields), opts.model.__name__)
+                message %= (", ".join(missing_fields), opts.model.__name__)
                 raise FieldError(message)
             # Override default model fields with any custom declared ones
             # (plus, include all the other declared fields).
diff --git a/django/forms/widgets.py b/django/forms/widgets.py
index 96cb910273..c5c531ada7 100644
--- a/django/forms/widgets.py
+++ b/django/forms/widgets.py
@@ -207,7 +207,7 @@ def media_property(cls):
                 else:
                     m = Media()
                     for medium in extend:
-                        m = m + base[medium]
+                        m += base[medium]
                 return m + Media(definition)
             return Media(definition)
         return base
@@ -945,7 +945,7 @@ class MultiWidget(Widget):
         """
         media = Media()
         for w in self.widgets:
-            media = media + w.media
+            media += w.media
         return media
 
     media = property(_get_media)
diff --git a/django/http/response.py b/django/http/response.py
index 7c0db55a5d..bb94e81263 100644
--- a/django/http/response.py
+++ b/django/http/response.py
@@ -241,7 +241,7 @@ class HttpResponseBase:
                 # Add one second so the date matches exactly (a fraction of
                 # time gets lost between converting to a timedelta and
                 # then the date string).
-                delta = delta + datetime.timedelta(seconds=1)
+                delta += datetime.timedelta(seconds=1)
                 # Just set max_age - the max_age logic will set expires.
                 expires = None
                 if max_age is not None:
diff --git a/django/middleware/security.py b/django/middleware/security.py
index 1dd2204814..52c81e3406 100644
--- a/django/middleware/security.py
+++ b/django/middleware/security.py
@@ -38,9 +38,9 @@ class SecurityMiddleware(MiddlewareMixin):
         ):
             sts_header = "max-age=%s" % self.sts_seconds
             if self.sts_include_subdomains:
-                sts_header = sts_header + "; includeSubDomains"
+                sts_header += "; includeSubDomains"
             if self.sts_preload:
-                sts_header = sts_header + "; preload"
+                sts_header += "; preload"
             response.headers["Strict-Transport-Security"] = sts_header
 
         if self.content_type_nosniff:
diff --git a/django/templatetags/i18n.py b/django/templatetags/i18n.py
index 8b4824fbbf..b26cc701b4 100644
--- a/django/templatetags/i18n.py
+++ b/django/templatetags/i18n.py
@@ -187,7 +187,7 @@ class BlockTranslateNode(Node):
         data = {v: render_value(v) for v in vars}
         context.pop()
         try:
-            result = result % data
+            result %= data
         except (KeyError, ValueError):
             if nested:
                 # Either string is malformed, or it's a bug
diff --git a/django/test/utils.py b/django/test/utils.py
index 270e34b69d..2b2b92c593 100644
--- a/django/test/utils.py
+++ b/django/test/utils.py
@@ -593,7 +593,7 @@ class modify_settings(override_settings):
                 if isinstance(items, str):
                     items = [items]
                 if action == "append":
-                    value = value + [item for item in items if item not in value]
+                    value += [item for item in items if item not in value]
                 elif action == "prepend":
                     value = [item for item in items if item not in value] + value
                 elif action == "remove":
diff --git a/django/urls/base.py b/django/urls/base.py
index 647ef3e2de..753779c75b 100644
--- a/django/urls/base.py
+++ b/django/urls/base.py
@@ -70,7 +70,7 @@ def reverse(viewname, urlconf=None, args=None, kwargs=None, current_app=None):
             try:
                 extra, resolver = resolver.namespace_dict[ns]
                 resolved_path.append(ns)
-                ns_pattern = ns_pattern + extra
+                ns_pattern += extra
                 ns_converters.update(resolver.pattern.converters)
             except KeyError as key:
                 if resolved_path:
diff --git a/django/utils/datetime_safe.py b/django/utils/datetime_safe.py
index 817ddcf0fa..2792b48a26 100644
--- a/django/utils/datetime_safe.py
+++ b/django/utils/datetime_safe.py
@@ -95,10 +95,10 @@ def strftime(dt, fmt):
     # 6 years to get into the 28-year repeat cycle
     delta = 2000 - year
     off = 6 * (delta // 100 + delta // 400)
-    year = year + off
+    year += off
 
     # Move to around the year 2000
-    year = year + ((2000 - year) // 28) * 28
+    year += ((2000 - year) // 28) * 28
     timetuple = dt.timetuple()
     s1 = time.strftime(fmt, (year,) + timetuple[1:])
     sites1 = _findall(s1, str(year))
diff --git a/django/utils/duration.py b/django/utils/duration.py
index 8495af3fa8..eae8527710 100644
--- a/django/utils/duration.py
+++ b/django/utils/duration.py
@@ -7,10 +7,10 @@ def _get_duration_components(duration):
     microseconds = duration.microseconds
 
     minutes = seconds // 60
-    seconds = seconds % 60
+    seconds %= 60
 
     hours = minutes // 60
-    minutes = minutes % 60
+    minutes %= 60
 
     return days, hours, minutes, seconds, microseconds
 
diff --git a/django/utils/numberformat.py b/django/utils/numberformat.py
index 6e3628ff91..a1ecd1bd0d 100644
--- a/django/utils/numberformat.py
+++ b/django/utils/numberformat.py
@@ -81,7 +81,7 @@ def format(
     else:
         int_part, dec_part = str_number, ""
     if decimal_pos is not None:
-        dec_part = dec_part + ("0" * (decimal_pos - len(dec_part)))
+        dec_part += "0" * (decimal_pos - len(dec_part))
     dec_part = dec_part and decimal_sep + dec_part
     # grouping
     if use_grouping:
diff --git a/django/utils/timezone.py b/django/utils/timezone.py
index 2107ec96ae..f3eac0e7b2 100644
--- a/django/utils/timezone.py
+++ b/django/utils/timezone.py
@@ -334,7 +334,7 @@ def _is_pytz_zone(tz):
     _PYTZ_BASE_CLASSES = (pytz.tzinfo.BaseTzInfo, pytz._FixedOffset)
     # In releases prior to 2018.4, pytz.UTC was not a subclass of BaseTzInfo
     if not isinstance(pytz.UTC, pytz._FixedOffset):
-        _PYTZ_BASE_CLASSES = _PYTZ_BASE_CLASSES + (type(pytz.UTC),)
+        _PYTZ_BASE_CLASSES += (type(pytz.UTC),)
 
     return isinstance(tz, _PYTZ_BASE_CLASSES)
 
diff --git a/django/utils/translation/__init__.py b/django/utils/translation/__init__.py
index 6b8cc73d5c..0b3f78e486 100644
--- a/django/utils/translation/__init__.py
+++ b/django/utils/translation/__init__.py
@@ -149,7 +149,7 @@ def lazy_number(func, resultclass, number=None, **kwargs):
                     number_value = rhs
                 translated = self._translate(number_value)
                 try:
-                    translated = translated % rhs
+                    translated %= rhs
                 except TypeError:
                     # String doesn't contain a placeholder for the number.
                     pass
diff --git a/tests/admin_inlines/tests.py b/tests/admin_inlines/tests.py
index ad7446e1ca..73f888d9d3 100644
--- a/tests/admin_inlines/tests.py
+++ b/tests/admin_inlines/tests.py
@@ -1908,11 +1908,9 @@ class SeleniumTests(AdminSeleniumTestCase):
             "border-top-%s",
         ]
         for prop in border_properties:
-            prop = prop % "width"
-            self.assertEqual(element.value_of_css_property(prop), width)
+            self.assertEqual(element.value_of_css_property(prop % "width"), width)
         for prop in border_properties:
-            prop = prop % "style"
-            self.assertEqual(element.value_of_css_property(prop), style)
+            self.assertEqual(element.value_of_css_property(prop % "style"), style)
         # Convert hex color to rgb.
         self.assertRegex(color, "#[0-9a-f]{6}")
         r, g, b = int(color[1:3], 16), int(color[3:5], 16), int(color[5:], 16)
@@ -1923,8 +1921,7 @@ class SeleniumTests(AdminSeleniumTestCase):
             "rgba(%d, %d, %d, 1)" % (r, g, b),
         ]
         for prop in border_properties:
-            prop = prop % "color"
-            self.assertIn(element.value_of_css_property(prop), colors)
+            self.assertIn(element.value_of_css_property(prop % "color"), colors)
 
     def test_inline_formset_error_input_border(self):
         from selenium.webdriver.common.by import By
diff --git a/tests/forms_tests/tests/test_media.py b/tests/forms_tests/tests/test_media.py
index 171b70e508..aa508cb415 100644
--- a/tests/forms_tests/tests/test_media.py
+++ b/tests/forms_tests/tests/test_media.py
@@ -643,7 +643,7 @@ class FormsMediaTestCase(SimpleTestCase):
         self.assertEqual(
             merged._css, {"screen": ["c.css", "a.css"], "all": ["d.css", "e.css"]}
         )
-        merged = merged + widget3
+        merged += widget3
         # widget3 contains an explicit ordering of c.css and a.css.
         self.assertEqual(
             merged._css,
diff --git a/tests/migrations/test_loader.py b/tests/migrations/test_loader.py
index 847b937d5a..800d715bc9 100644
--- a/tests/migrations/test_loader.py
+++ b/tests/migrations/test_loader.py
@@ -390,7 +390,7 @@ class LoaderTests(TestCase):
         loader.build_graph()
 
         plan = set(loader.graph.forwards_plan(("app1", "4_auto")))
-        plan = plan - loader.applied_migrations.keys()
+        plan -= loader.applied_migrations.keys()
         expected_plan = {
             ("app2", "1_squashed_2"),
             ("app1", "3_auto"),
@@ -529,7 +529,7 @@ class LoaderTests(TestCase):
         # Load with nothing applied: both migrations squashed.
         loader.build_graph()
         plan = set(loader.graph.forwards_plan(("app1", "4_auto")))
-        plan = plan - loader.applied_migrations.keys()
+        plan -= loader.applied_migrations.keys()
         expected_plan = {
             ("app1", "1_auto"),
             ("app2", "1_squashed_2"),
@@ -548,7 +548,7 @@ class LoaderTests(TestCase):
         loader.replace_migrations = False
         loader.build_graph()
         plan = set(loader.graph.forwards_plan(("app1", "3_auto")))
-        plan = plan - loader.applied_migrations.keys()
+        plan -= loader.applied_migrations.keys()
         expected_plan = {
             ("app1", "1_auto"),
             ("app2", "1_auto"),
@@ -564,7 +564,7 @@ class LoaderTests(TestCase):
         self.record_applied(recorder, "app1", "2_auto")
         loader.build_graph()
         plan = set(loader.graph.forwards_plan(("app1", "4_auto")))
-        plan = plan - loader.applied_migrations.keys()
+        plan -= loader.applied_migrations.keys()
         expected_plan = {
             ("app2", "1_squashed_2"),
             ("app1", "3_auto"),
@@ -576,7 +576,7 @@ class LoaderTests(TestCase):
         self.record_applied(recorder, "app2", "1_auto")
         loader.build_graph()
         plan = set(loader.graph.forwards_plan(("app1", "4_auto")))
-        plan = plan - loader.applied_migrations.keys()
+        plan -= loader.applied_migrations.keys()
         expected_plan = {
             ("app2", "2_auto"),
             ("app1", "3_auto"),