Standardize exception handling

lib/ansible/cache/base.py

@@ -1,18 +1,21 @@
+import exceptions
+
 class BaseCacheModule(object):
+
     def get(self, key):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError
 
     def set(self, key, value):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError
 
     def keys(self):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError
 
     def contains(self, key):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError
 
     def delete(self, key):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError
 
     def flush(self):
-        raise NotImplementedError("Subclasses of {} must implement the '{}' method".format(self.__class__.__name__, self.__name__))
+        raise exceptions.NotImplementedError