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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 enable_node(self, service_name, node_name):
 """ Enables a given node name for the given service name via the "enable server" HAProxy command. """

        logger.info("Enabling server %s/%s", service_name, node_name)
        return self.send_command(
            "enable server %s/%s" % (service_name, node_name)
        )