python,通过创建类实现多线程例子

import threading,time
class MyThread(threading.Thread):
    def __init__(self,num):
        threading.Thread.__init__(self)
        self.num = num
    def run(self):
        print("running on number:%s"%self.num)
        time.sleep(self.num)

if __name__ == ‘__main__‘:
    begin = time.time()
    t1 = MyThread(1)
    t2 = MyThread(2)
    t1.start()
    t2.start()
    t1.join()
    t2.join()
    end = time.time()
    print(end - begin)