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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 set(self, time_sec, callback_fn, *args, **kwdargs):
 """Convenience function to create and set a timer. Equivalent to: timer = timer_factory.timer() timer.set_callback('expired', callback_fn, *args, **kwdargs) timer.set(time_sec) """

        timer = self.timer()
        timer.set_callback('expired', callback_fn, *args, **kwdargs)
        timer.set(time_sec)
        return timer