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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 lap(self):
 """Calculate lap time. Returns: float: Lap time. The duration from the previous call of ``lap()`` or initialization at first call. float: Total time. The duration from initialization. """

        now = time.time()
        lap_time = now - self.lap_time
        total_time = now - self.start
        self.lap_time = now
        return lap_time, total_time