python client heartbeat failed about nacos HOT 7 CLOSED

# Not working: 这个方法发不出心跳
NacosClient.send_heartbeat(service_name, ip, port, cluster_name, weight, metadata)

class NacosManager:

    def __init__(self, nacos_cfg: NacosConfig = None):
        if nacos_cfg is None:
            nacos_cfg = NacosConfig()
        
        self.nacos_cfg = nacos_cfg

        self.service_host: str = find_this_host()       #服务注册的地址
        self.service_port: int = find_free_port()       #服务注册的端口

        # Nacos的交互实例
        self.client = NacosClient(
            server_addresses = self.nacos_cfg.server_addresses,
            namespace = self.nacos_cfg.namespace_id
        )

    def register(self) -> None:
        """
        注册服务到nacos
        """
        self.client.add_naming_instance(
            service_name = self.nacos_cfg.service_name,
            ip = self.service_host,
            port = self.service_port,
            cluster_name = self.nacos_cfg.service_cluster_name,
            group_name = self.nacos_cfg.group_name
        )

   def heartbeat(self) -> None:
        """
        异步发送心跳
        """

        while True:
            # FIXME: 发送心跳不管用，因为nacos是2.04版本，这个sdk不支持，所以改成5秒钟注册一次
            self.register()
            time.sleep(5)