code: def enable_node(self, service_name, node_name):
          
          logger.info("Enabling server %s/%s", service_name, node_name)
          return self.send_command(
              "enable server %s/%s" % (service_name, node_name)
          )
docs: Enables a given node name for the given service name via the
          "enable server" HAProxy command.