实用：python中的协程开发简单语法

import asyncio

@asyncio.coroutine
def a():
    for x in range(3):
        print('a',x)
        yield

@asyncio.coroutine
def b():
    for x in range(3):
        print('b',x)
        yield

loop = asyncio.get_event_loop()
tasks = [a(),b()]
loop.run_until_complete(asyncio.wait(tasks))

# loop.close()

print('===========================')

async def a(x):
    for i in range(3):
        print('a {}'.format(i))
        await asyncio.sleep(x)

async def b(x):
    for i in range(3):
        print('b {}'.format(i))
        await asyncio.sleep(x)

loop = asyncio.get_event_loop()
tasks = [a(1),b(1)]
loop.run_until_complete(asyncio.wait(tasks))
loop.close()

运行结果：

a 0
b 0
a 1
b 1
a 2
b 2
===========================
a 0
b 0
a 1
b 1
a 2
b 2