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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 _finalize_db(self):
 """Convert defaultdicts to regular dicts."""

        for k, v in self._els_idxed.items():
            self._els_idxed[k] = dict(v)
        self._els_idxed = dict(self._els_idxed)