How to use the node-opcua-service-discovery._announcedOnMulticastSubnet function in node-opcua-service-discovery

super.start((err) => {
            if (!err) {
                // declare server in bonjour
                _announcedOnMulticastSubnet(this, {
                    applicationUri: this.serverInfo.applicationUri,
                    port: this.endpoints[0].port,
                    path: "/DiscoveryServer",
                    capabilities: this.capabilitiesForMDNS
                });
                //
                this.mDnsResponder = new MDNSResponser();

            }
            done(err);
        });
    }