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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 timer_tick(self):
 """Callback executed every self.base_interval_msec to check timer expirations. """

        # TODO: should exceptions thrown from this be caught and ignored
        self.process_timers()

        delta = datetime.timedelta(milliseconds=self.base_interval_msec)
        self._timeout = IOLoop.current().add_timeout(delta, self.timer_tick)