import threading # 加锁 metux = threading.Lock() age = 0 class Metux(object):     def f1(self):         global age         for i in range(10):             metux.acquire()             age = age + i             metux.release()             print(age)     def f2(self):         for i in range(11):             global age             metux.acquire()             age = age + i             metux.release()             print(age) if __name__ == '__main__':     m = Metux()     t1 = threading.Thread(target=m.f1())     t2 = threading.Thread(target=m.f2())     t1.start()     t2.start()