Used "is" for comparisons with None.

1 files changed, 1 insertions, 1 deletions

diff --git a/django/middleware/cache.py b/django/middleware/cache.py
index 55b61358ea..dbd5b80fb2 100644
--- a/django/middleware/cache.py
+++ b/django/middleware/cache.py
@@ -96,7 +96,7 @@ class UpdateCacheMiddleware(object):
         # Control" header before reverting to using the default cache_timeout
         # length.
         timeout = get_max_age(response)
-        if timeout == None:
+        if timeout is None:
             timeout = self.cache_timeout
         elif timeout == 0:
             # max-age was set to 0, don't bother caching.