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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 get_xmlrpc_server(self):
 """ Returns PyPI's XML-RPC server instance """

        check_proxy_setting()
        if os.environ.has_key('XMLRPC_DEBUG'):
            debug = 1
        else:
            debug = 0
        try:
            return xmlrpclib.Server(XML_RPC_SERVER, transport=ProxyTransport(), verbose=debug)
        except IOError:
            self.logger("ERROR: Can't connect to XML-RPC server: %s" \
                    % XML_RPC_SERVER)