diff --git a/rest_framework/exceptions.py b/rest_framework/exceptions.py
index 5dd6b35fe..7e4449deb 100644
--- a/rest_framework/exceptions.py
+++ b/rest_framework/exceptions.py
@@ -86,7 +86,6 @@ class ErrorDetail(str):
     def __repr__(self):
         return f"ErrorDetail(string='{str(self)}', code='{self.code}')"
 
-
     def __hash__(self):
         return hash(str(self))
 
diff --git a/rest_framework/filters.py b/rest_framework/filters.py
index 31fcf283f..d667a3826 100644
--- a/rest_framework/filters.py
+++ b/rest_framework/filters.py
@@ -236,9 +236,9 @@ class OrderingFilter(BaseFilterBackend):
             (field.source.replace('.', '__') or field_name, field.label)
             for field_name, field in serializer_class(context=context).fields.items()
             if (
-                    not getattr(field, 'write_only', False) and
-                    not field.source == '*' and
-                    field.source not in model_property_names
+                not getattr(field, 'write_only', False) and
+                not field.source == '*' and
+                field.source not in model_property_names
             )
         ]
 
diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index 3de6a6385..a80a51ee4 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -411,9 +411,9 @@ class HyperlinkedRelatedField(RelatedField):
             if value in ('', None):
                 value_string = {'': 'the empty string', None: 'None'}[value]
                 msg += (
-                        " WARNING: The value of the field on the model instance "
-                        f"was {value_string}, which may be why it didn't match any "
-                        "entries in your URL conf."
+                    " WARNING: The value of the field on the model instance "
+                    f"was {value_string}, which may be why it didn't match any "
+                    "entries in your URL conf."
                 )
             raise ImproperlyConfigured(msg % self.view_name)
 
diff --git a/rest_framework/request.py b/rest_framework/request.py
index 324188396..0189f5c89 100644
--- a/rest_framework/request.py
+++ b/rest_framework/request.py
@@ -153,8 +153,7 @@ class Request:
                  negotiator=None, parser_context=None):
         assert isinstance(request, HttpRequest), (
             'The `request` argument must be an instance of '
-            '`django.http.HttpRequest`, not `{}.{}`.'
-                .format(request.__class__.__module__, request.__class__.__name__)
+            f'`django.http.HttpRequest`, not `{request.__class__.__module__}.{request.__class__.__name__}`.' # noqa
         )
 
         self._request = request
diff --git a/rest_framework/templatetags/rest_framework.py b/rest_framework/templatetags/rest_framework.py
index 0dbaa196e..8e35fec6e 100644
--- a/rest_framework/templatetags/rest_framework.py
+++ b/rest_framework/templatetags/rest_framework.py
@@ -219,7 +219,7 @@ def format_value(value):
     elif isinstance(value, str):
         if (
                 (value.startswith('http:') or value.startswith('https:')) and not
-        re.search(r'\s', value)
+                re.search(r'\s', value)
         ):
             return mark_safe('<a href="{value}">{value}</a>'.format(value=escape(value)))
         elif '@' in value and not re.search(r'\s', value):
diff --git a/tests/test_exceptions.py b/tests/test_exceptions.py
index 472e27e5f..3564a2698 100644
--- a/tests/test_exceptions.py
+++ b/tests/test_exceptions.py
@@ -70,9 +70,9 @@ class ErrorDetailTests(TestCase):
 
     def test_repr(self):
         assert repr(ErrorDetail('msg1')) == \
-            f"ErrorDetail(string='msg1', code='None')"
+            "ErrorDetail(string='msg1', code='None')"
         assert repr(ErrorDetail('msg1', 'code')) == \
-            f"ErrorDetail(string='msg1', code='code')"
+            "ErrorDetail(string='msg1', code='code')"
 
     def test_str(self):
         assert str(ErrorDetail('msg1')) == 'msg1'