在python中停止一个线程，为什么以下不起作用？

Question

我一直在努力提供阻止this thread 之后的线程的功能。我有以下课程：

class WorkerThread(threading.Thread):
    """Thread class with a stop() method. The thread itself has to check
    regularly for the stopped() condition."""

    def __init__(self, id):
        super(WorkerThread, self).__init__()
        self._id = id
        self._stop = threading.Event()

    def stop(self):
        self._stop.set()

    def stopped(self):
        return self._stop.isSet()

    def run(self):
        while not self.stopped():
            print ("Thread with id {0} Running".format(self._id))
            time.sleep(1)

当我创建10个线程并试图阻止它们时，它们都不会停止并继续打印。

threads = [WorkerThread(x) for x in range(10)]
[thread.start() for thread in threads]
time.sleep(2) #wait
[thread.stop() for thread in threads]
[thread.join() for thread in threads]
print "All done" #never printed

有人可以解释为什么忽略停止事件？我还尝试将_stop属性用作标记，并在__init__和True stop()中将其设置为false，但没有运气。