gistfile1.py

import asyncio

async def worker():
    fut = asyncio.Future()

    def setval():
        print('setval')
        fut.set_result(123)

    print('setup')
    loop.call_later(1.0, setval)
    print(await fut)

async def test():
    await worker()

loop = asyncio.get_event_loop()
loop.run_until_complete(test())