Exclude from __all__

Author: tjkuson

stdlib/asyncio/__init__.pyi

@@ -55,7 +55,6 @@ if sys.platform == "win32":
             "Server",  # from base_events
             "iscoroutinefunction",  # from coroutines
             "iscoroutine",  # from coroutines
-            "AbstractEventLoopPolicy",  # from events
             "AbstractEventLoop",  # from events
             "AbstractServer",  # from events
             "Handle",  # from events