event.wait() wait未被设定时，线程会被卡住，执行不下去，一旦设定，就相当于pass

event.set() 来给wait设定

event.clear() 来清除set设定

import threading
import time

class Boss(threading.Thread):
    def run(self):
        print("boss: 今晚加班到12.00")
        print(event.isSet())
        event.set()
        time.sleep(5)
        print("时间到了，下班了")
        print(event.isSet())
        event.set()
class Worker(threading.Thread):
    def run(self):
        event.wait()
        print("Worker:惨 啊")
        time.sleep(1)
        event.clear()
        event.wait()
        print("yes")               
if __name__ == '__main__':
    event = threading.Event()
    threads = []
    for i in range(5):
        threads.append(Worker())
    threads.append(Boss())
    for t in threads:
        t.start()
    for t in threads:
        t.join()