aiocron provide a decorator to run function at time:

>>> import aiocron
>>> import asyncio
>>>
>>> @aiocron.crontab('*/30 * * * *')
... async def attime():
...     print('run')
...
>>> asyncio.get_event_loop().run_forever()

You can also use it as an object:

>>> @aiocron.crontab('1 9 * * 1-5', start=False)
... async def attime():
...     print('run')
...
>>> attime.start()
>>> asyncio.get_event_loop().run_forever()

Your function still be available at attime.func

You can also await a crontab. In this case, your coroutine can accept arguments:

>>> @aiocron.crontab('0 9,10 * * * mon,fri', start=False)
... async def attime(i):
...     print('run %i' % i)
...
>>> async def once():
...     try:
...         res = await attime.next(1)
...     except Exception as e:
...         print('It failed (%r)' % e)
...     else:
...         print(res)
...
>>> asyncio.get_event_loop().run_forever()

Finally you can use it as a sleep coroutine. The following will wait until next hour:

>>> await crontab('0 * * * *').next()

If you don't like the decorator magic you can set the function by yourself:

>>> cron = crontab('0 * * * *', func=yourcoroutine, start=False)

Notice that unlike standard unix crontab you can specify seconds at the 6th position.

aiocron use croniter. Refer to it's documentation to know more about crontab format.