diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 64ec37770f..8bb131a047 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -13,7 +13,7 @@ repos:
   hooks:
   - id: isort
 - repo: https://github.com/PyCQA/flake8
-  rev: 3.9.0
+  rev: 5.0.0
   hooks:
   - id: flake8
     additional_dependencies:
diff --git a/rest_framework/decorators.py b/rest_framework/decorators.py
index 3b572c09ef..6194817563 100644
--- a/rest_framework/decorators.py
+++ b/rest_framework/decorators.py
@@ -36,7 +36,7 @@ def decorator(func):
         #     WrappedAPIView.__doc__ = func.doc    <--- Not possible to do this
 
         # api_view applied without (method_names)
-        assert not(isinstance(http_method_names, types.FunctionType)), \
+        assert not (isinstance(http_method_names, types.FunctionType)), \
             '@api_view missing list of allowed HTTP methods'
 
         # api_view applied with eg. string instead of list of strings
diff --git a/tests/test_throttling.py b/tests/test_throttling.py
index d5a61232d9..be9decebc5 100644
--- a/tests/test_throttling.py
+++ b/tests/test_throttling.py
@@ -192,7 +192,7 @@ def ensure_response_header_contains_proper_throttle_field(self, view, expected_h
             if expect is not None:
                 assert response['Retry-After'] == expect
             else:
-                assert not'Retry-After' in response
+                assert 'Retry-After' not in response
 
     def test_seconds_fields(self):
         """