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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 drop(self, relation):
 """Drop the named relation and cascade it appropriately to all dependent relations. that are noops, nonexistent relation drops cause a debug log and no other actions. :param str schema: The schema of the relation to drop. :param str identifier: The identifier of the relation to drop. """

        dropped = _make_key(relation)
        logger.debug('Dropping relation: {!s}'.format(dropped))
        with self.lock:
            self._drop_cascade_relation(dropped)