Fixed #28397 -- Removed django.core.exceptions.DjangoRuntimeWarning.

django/core/cache/backends/base.py

@@ -2,7 +2,7 @@
 import time
 import warnings
 
-from django.core.exceptions import DjangoRuntimeWarning, ImproperlyConfigured
+from django.core.exceptions import ImproperlyConfigured
 from django.utils.module_loading import import_string
 
 
@@ -10,7 +10,7 @@ class InvalidCacheBackendError(ImproperlyConfigured):
     pass
 
 
-class CacheKeyWarning(DjangoRuntimeWarning):
+class CacheKeyWarning(RuntimeWarning):
     pass
 
 

django/core/exceptions.py

@@ -8,10 +8,6 @@ class FieldDoesNotExist(Exception):
     pass
 
 
-class DjangoRuntimeWarning(RuntimeWarning):
-    pass
-
-
 class AppRegistryNotReady(Exception):
     """The django.apps registry is not populated yet"""
     pass

docs/releases/2.0.txt

@@ -547,6 +547,10 @@ Miscellaneous
   <automatic-spatial-transformations>` now raises ``NotImplementedError``
   on MySQL instead of silently using non-transformed geometries.
 
+* ``django.core.exceptions.DjangoRuntimeWarning`` is removed. It was only used
+  in the cache backend as an intermediate class in ``CacheKeyWarning``'s
+  inheritance of ``RuntimeWarning``.
+
 .. _deprecated-features-2.0:
 
 Features deprecated in 2.0