异步发展过程

1.用greenlet

from greenlet import greenletdef fun1():print('1')
def fun2():print('2')
g1=greenlet(fun1)
g2=greenlet(fun2)
g1.switch()

2.用yield

3.用asyncio

import asyncio
@asyncio.coroutine
def fun3():yield  from asyncio.sleep(2)print('3')
tasks=[asyncio.ensure_future(fun3())]asyncio.get_event_loop().run_until_complete(asyncio.wait(tasks))
第三阶段也就是上面的第三条最后一步，随着python不断更新对第三阶段的的最后一步实现了简写

async def main():tasks = [asyncio.ensure_future(fun4())]done,pending= await asyncio.wait(tasks,timeout=None)print(done)
# 此方法 在run方法中实get_event_loop().run_until_complete(asyncio.wait(tasks))
asyncio.run(main())