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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 clean_out_user(self, name_id):
 """ Remove all authentication statements that belongs to a user identified by a NameID instance :param name_id: NameID instance :return: The local identifier for the user """


        lid = self.ident.find_local_id(name_id)
        logger.info("Clean out %s", lid)

        # remove the authentications
        try:
            for _nid in [decode(x) for x in self.ident.db[lid].split(" ")]:
                try:
                    self.session_db.remove_authn_statements(_nid)
                except KeyError:
                    pass
        except KeyError:
            pass

        return lid