Mocking async call in python 3.5

The solution was actually quite simple:
I just needed to convert __call__ method of mock into coroutine:

class AsyncMock(MagicMock):
    async def __call__(self, *args, **kwargs):
        return super(AsyncMock, self).__call__(*args, **kwargs)

This works perfectly, when mock is called, code receives native coroutine

Example usage:

@mock.patch('my.path.asyncio.sleep', new_callable=AsyncMock)
def test_stuff(sleep):
    # code