Python线程锁

#-*- coding:utf-8 -*-
__author__ = "MuT6 Sch01aR"

import threading
import time

num = 0
t_obj = []
lock = threading.Lock() #声明一个锁并赋给一个变量

def MyThread(n):
    lock.acquire() #给线程加锁
    global num
    time.sleep(0.5)
    num +=1
    lock.release() #释放给线程锁

for i in range(20):
    t = threading.Thread(target=MyThread,args=(i,))
    t.start()
    t_obj.append(t)

for t in t_obj:
    t.join()

print("num:",num)