With current version of `mypy` any project using `AsyncioExecutor` with `loop=` argument provided as follows: ```Python executor = AsyncioExecutor(loop=asyncio.get_event_loop()) ``` fails type check with following error ``` ***: error: Argument "loop" to "AsyncioExecutor" has incompatible type "AbstractEventLoop"; expected "Optional[_UnixSelectorEventLoop]" ``` Basically `asyncio.get_event_loop()` returns `asyncio.AbstractEventLoop` object, and AsyncioExecutor expects `asyncio._UnixSelectorEventLoop`. type definition: https://github.com/graphql-python/graphql-core-legacy/blob/26b0fc085170e8a56a7672092fdcf8621e6d6348/graphql/execution/executors/asyncio.py#L54