async_manager.py

import asyncio


class Manager:
    async def __aenter__(self):
        print("aenter")
        return object()

    async def __aexit__(self, *exc_info):
        print("aexit")


async def get_obj():
    async with Manager() as obj:
        yield obj


async def main():
    async for obj in get_obj():
        raise Exception


if __name__ == "__main__":
    loop = asyncio.get_event_loop()
    loop.run_until_complete(main())
    # print aenter and Exception