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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 timezone(self, timezone=0):
 """ Sets the timezone of the entire track Args: timezone (int):
 Timezone hour delta """

        tz_dt = timedelta(hours=timezone)
        for segment in self.segments:
            for point in segment.points:
                point.time = point.time + tz_dt
        return self