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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 getPeer(self, url):
 """ Select the first peer in the datarepo with the given url simulating the behavior of selecting by URL. This is only used during testing. """

        peers = filter(lambda x: x.getUrl() == url, self.getPeers())
        if len(peers) == 0:
            raise exceptions.PeerNotFoundException(url)
        return peers[0]