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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 connectPeer(self, peer):
 """Establish a SIGMA connection to the given peer. @param peer: a Q2QAddress of a peer which has a file that I want @return: a Deferred which fires a SigmaProtocol. """

        return self.conns.connectCached(endpoint.Q2QEndpoint(self.svc,
                                                             self.addr,
                                                             peer,
                                                             PROTOCOL_NAME),
                                        self.clientFactory)