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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 _get_db_fields(self, obj):
 """ Return list of database dictionaries, which are used as indexes for each attributes. Args: cached (bool, default True):
 Use cached connection to database. Returns: list: List of OOBTree's for each item in :attr:`.COMMON_FIELDS`. """

        for field in obj.indexes:
            yield field, self._zeo_key(field)