分别运行以下每一部分代码，可以查看效果。

#! /usr/bin/env python
#coding=utf-8
import threading
import time
'''
#1、不加锁
num = 0
class MyThread(threading.Thread):
    def run(self):
        global num
        time.sleep(1) #一定要sleep！！！
        num = num + 1
        msg = self.name + ' num is ---- ' + str(num)
        print msg

def test():
    for i in range(10):
        s = MyThread() #实例化一个Thread对象，每个Thread对象代表着一个线程
        s.start()  #通过start()方法，开始线程活动
'''
#'''
class MyThread(threading.Thread):
    def run(self):
        for i in range(3):
            time.sleep(1)
            msg = self.name+' @ '+str(i)
            print msg
def test():
    for i in range(5):
        t = MyThread()
        t.start()
#'''
'''
#2、加锁
num = 0 #多个线程共享操作的数据
mu = threading.Lock() #创建一个锁
class MyThread(threading.Thread):
    def run(self):
        global num
        time.sleep(1)
        if mu.acquire(True): #获取锁状态，一个线程有锁时，别的线程只能在外面等着
            num = num + 1
            msg = self.name + ' num is ---- ' + str(num)
            print msg
            mu.release() #释放锁

def test():
    for i in range(10):
        s = MyThread()
        s.start()
'''

if __name__ == '__main__':

    test()