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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 base_station(self):
 """Return the base_station assigned for the given camera."""

        try:
            return list(filter(lambda x: x.device_id == self.parent_id,
                               self._session.base_stations))[0]
        except (IndexError, AttributeError):
            return None