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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 defragment(self):
 """Defragment a member's backend database to recover storage space."""

        defrag_request = etcdrpc.DefragmentRequest()
        self.maintenancestub.Defragment(
            defrag_request,
            self.timeout,
            credentials=self.call_credentials,
            metadata=self.metadata
        )