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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 id_range(self):
 """Get the range of archor reading_ids. Returns: (int, int):
 The lowest and highest reading ids. If no reading ids have been loaded, (0, 0) is returned. """


        if len(self._anchor_points) == 0:
            return (0, 0)

        return (self._anchor_points[0].reading_id, self._anchor_points[-1].reading_id)