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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 reset(self, period=None):
 """ Reset the internal timer, effectively causing the next tick to happen in `self.period` seconds. :param period: If not `None`, specifies a new period to use. """

        if period is not None:
            self.period = period

        self.reset_event.set()