Thread Based Parallelism - Thread in a Subclass

　　  1     import threading 2     import time 3  4     exit_Flag = 0 5  6     class myThread (threading.Thread): 7         def __init__(self, threadID, name, counter): 8             threading.Thread.__init__(self) 9             self.threadID = threadID10             self.name = name11             self.counter = counter12         def run(self):13             print ("Starting " + self.name + "\n")14             print_time(self.name, self.counter, 5)15             print ("Exiting " + self.name + "\n")16 17     def print_time(threadName, delay, counter):18         while counter:19             if exit_Flag:20                 thread.exit()21             time.sleep(delay)22             print ("%s: %s" % (threadName, time.ctime(time.time())))23             counter -= 124 25     if __name__ == '__main__':26         # Create two threads27         thread1 = myThread(1, "Thread-1", 1)28         thread2 = myThread(2, "Thread-2", 2)29 30         # Start the Threads created31         thread1.start()32         thread2.start()33 34         # Wait for all thread to complete35         thread1.join()36         thread2.join()37 38         print ("Exiting Main Thread")39 40     Output,41         Starting Thread-142         Starting Thread-243 44         Thread-1: Thu Feb  8 15:08:47 201845         Thread-1: Thu Feb  8 15:08:48 201846         Thread-2: Thu Feb  8 15:08:48 201847         Thread-1: Thu Feb  8 15:08:49 201848         Thread-2: Thu Feb  8 15:08:50 201849         Thread-1: Thu Feb  8 15:08:50 201850         Thread-1: Thu Feb  8 15:08:51 201851         Exiting Thread-152 53         Thread-2: Thu Feb  8 15:08:52 201854         Thread-2: Thu Feb  8 15:08:54 201855         Thread-2: Thu Feb  8 15:08:56 201856         Exiting Thread-257 58         Exiting Main Thread