more fixes for django stubs, first attempt for a plugin

django-stubs/core/cache/__init__.pyi

@@ -1,25 +1,32 @@
 from collections import OrderedDict
-from typing import Any, Callable, Dict, Optional, Union
+from typing import Any, Callable, Dict, Union
 
 from django.core.cache.backends.base import BaseCache as BaseCache
-from django.core.cache.backends.base import CacheKeyWarning as CacheKeyWarning
-from django.core.cache.backends.base import \
-    InvalidCacheBackendError as InvalidCacheBackendError
 
 DEFAULT_CACHE_ALIAS: str
 
+
 class CacheHandler:
     def __init__(self) -> None: ...
+
     def __getitem__(self, alias: str) -> BaseCache: ...
+
     def all(self): ...
 
+
 class DefaultCacheProxy:
     def __getattr__(
-        self, name: str
+            self, name: str
     ) -> Union[Callable, Dict[str, float], OrderedDict, int]: ...
+
     def __setattr__(self, name: str, value: Callable) -> None: ...
+
     def __delattr__(self, name: Any): ...
+
     def __contains__(self, key: str) -> bool: ...
+
     def __eq__(self, other: Any): ...
 
+
 cache: Any
+caches: CacheHandler