#!/usr/bin/python
# -*- coding: utf-8 -*-
from __future__ import print_function
import threading

lock = threading.Lock()
num = 0

def incre(count):
    global num
    while count>0:
        with lock:
            num += 1
        count -=1

def main():
    threads = []
    for i in range(10):
        thread = threading.Thread(target=incre,args=(1000000
 
,))
        thread.start();
        threads.append(thread)

    for thread in threads:
        thread.join()

    print('expected value is ', 10*1000000,'real value is',num)

if __name__ == '__main__':
    main()