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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 open(self):
 """Open connection and return proxy."""

        if not self.proxy:
            if not config.scgi_url:
                config.engine.load_config()
            if not config.scgi_url:
                self.LOG.error("You need to configure a XMLRPC connection, read"
                    " https://pyrocore.readthedocs.io/en/latest/setup.html")
            self.proxy = xmlrpc.RTorrentProxy(config.scgi_url)
            self.proxy._set_mappings()
        return self.proxy