greenlet实现协程

#greenlet
 1 import time
from greenlet import greenlet
# greenlet可以实现一个自行调度的微线程
def work1():
    while True:
        print("正在执行work1（）")
        time.sleep(0.5)#模拟阻塞
        # 如果遇到阻塞的情况下，切换到第二个任务
        g2.switch()

def work2():
    while True:
        print("正在执行work2（）")
        time.sleep(0.5)
        # 切换到第一个任务
        g1.switch()

if __name__ == '__main__':
    # 创建greenlet的对象    greenlet（函数名）
    g1 = greenlet(work1)
    g2 = greenlet(work2)
    g1.switch()