def related(self):
        """
        Iterator of :class:`stravalib.model.Activty` objects for activities matched as
        with this activity.
        """
        if self._related is None:
            if self.athlete_count - 1 > 0:
                self.assert_bind_client()
                self._related = self.bind_client.get_related_activities(self.id)
            else:
                self._related = []
        return self._related
Iterator of :class:`stravalib.model.Activty` objects for activities matched as
        with this activity.