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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 update_member(self, member_id, peer_urls):
 """ Update the configuration of an existing member in the cluster. :param member_id: ID of the member to update :param peer_urls: new list of peer urls the member will use to communicate with the cluster """

        member_update_request = etcdrpc.MemberUpdateRequest(ID=member_id,
                                                            peerURLs=peer_urls)
        self.clusterstub.MemberUpdate(
            member_update_request,
            self.timeout,
            credentials=self.call_credentials,
            metadata=self.metadata
        )