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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 compact(self, revision, physical=False):
 """ Compact the event history in etcd up to a given revision. All superseded keys with a revision less than the compaction revision will be removed. :param revision: revision for the compaction operation :param physical: if set to True, the request will wait until the compaction is physically applied to the local database such that compacted entries are totally removed from the backend database """

        compact_request = etcdrpc.CompactionRequest(revision=revision,
                                                    physical=physical)
        self.kvstub.Compact(
            compact_request,
            self.timeout,
            credentials=self.call_credentials,
            metadata=self.metadata
        )