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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 _delete_forever_keys(self):
 """ Delete all of the items that were stored forever. """

        for segment in self._tags.get_namespace().split('|'):
            segment = self._forever_key(segment)
            self._delete_forever_values(segment)

            self._store.connection().delete(segment)