Coroutines declared with async/await syntax is the preferred way of writing asyncio applications. For example, the following snippet of code (requires Python 3.7+) prints “hello”, waits 1 second, and

小结：

1、异步io  协程 

Coroutines and Tasks — Python 3.7.3 documentation https://docs.python.org/3/library/asyncio-task.htmlCoroutines and Tasks — Pyth