Python 无限循环

import threading
import time


class CountDownTimer(threading.Thread):
        def __init__(self, seconds, action):
            self.runTime = seconds
            self.action = action
            super(CountDownTimer, self).__init__()

        def run(self):
            counter = self.runTime
            for sec in range(self.runTime):
                    print counter
                    time.sleep(1.0)
                    counter -= 1
            print " Time's up"
            self.action()


def dosomethine():
    print "I'm ready"

    t = CountDownTimer(5, dosomethine)
    t.start()
if __name__ == "__main__":

    t = CountDownTimer(5, dosomethine)
    t.start()