If you are trying to use AsyncMock to mock a coroutine that returns awaitable objects, AsyncMock awaits on those objects instead of returning them as is. 

Example:
  mock = AsyncMock(return_value=asyncio.Future())
  v = await mock()  # blocks on trying to await the future

Expected:
  mock = AsyncMock(return_value=asyncio.Future())
  v = await mock()
  assert isisnstance(v, asyncio.Future)

This problem affects side_effects and wraps.