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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 _time_up(self):
 """ Called when the timer expires """

        self.running = False
        self.color = self.py3.COLOR_BAD
        self.time_left = 0
        self.done = True
        if self.sound:
            self.py3.play_sound(self.sound)
            self.alarm = True
        self.timer()