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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 get_athlete_stats(self, athlete_id=None):
 """ Returns Statistics for the athlete. athlete_id must be the id of the authenticated athlete or left blank. If it is left blank two requests will be made - first to get the authenticated athlete's id and second to get the Stats. http://strava.github.io/api/v3/athlete/#stats :return: A model containing the Stats :rtype: :py:class:`stravalib.model.AthleteStats` """

        if athlete_id is None:
            athlete_id = self.get_athlete().id

        raw = self.protocol.get('/athletes/{id}/stats', id=athlete_id)
        # TODO: Better error handling - this will return a 401 if this athlete
        #       is not the authenticated athlete.

        return model.AthleteStats.deserialize(raw)