import asyncio


@asyncio.coroutine
def countdown(name, num):
    while num > 0:
        print(f'Countdown[{name}]: {num}')
        yield from asyncio.sleep(1)
        num -= 1


def main():
    loop = asyncio.get_event_loop()
    tasks = [
        countdown("A", 10), countdown("B", 5),
    ]
    loop.run_until_complete(asyncio.wait(tasks))
    loop.close()


if __name__ == '__main__':
    main()