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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 _find_playlist(self):
 """ Internal method to populate the object given the ``id`` or ``reference_id`` that has been set in the constructor. """

        data = None
        if self.id:
            data = self.connection.get_item(
                'find_playlist_by_id', playlist_id=self.id)
        elif self.reference_id:
            data = self.connection.get_item(
                'find_playlist_by_reference_id',
                reference_id=self.reference_id)

        if data:
            self._load(data)