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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _start_check_timer(self):
 """ Periodically checks to see if the task has completed. """

        if self.timer:
            self.timer.cancel()
        self.timer = threading.Timer(2.5, self.check_complete)
        self.timer.daemon = True
        self.timer.start()