04 生成器版协程

import time

def f1():
    for i in range(10):
        time.sleep(0.5)
        print('f1>>',i)
        yield

def f2():
    g = f1()
    for i in range(10):
        time.sleep(0.5)
        print('f2>>', i)
        next(g)

f1()
f2()