i wonder how much of the code that is being created to be asyncio compatible is actually handling this error  since as far as i understand it  every usage of  yield from  needs to be wrapped in a  cancellederror and the code needs to handle this occurring though to what eventlet does that is similar being bad  since the code it monkey patches has no idea that a exception like  cancellederror  maybe raised  at least code created for asyncio should be somewhat aware that  cancellederror  s  may happen 