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console.log("Client started");const socket = new WebSocket("ws://localhost:3000/ws");
socket.addEventListener("open", () => {  socket.send("ping");  console.log("sent ping to server");});
socket.addEventListener("close", (_) => {  console.log("socket closed :(");});
socket.addEventListener("message", (e) => {  if (e.data === "ping") {    console.log("Received ping from server. Responding...");    socket.send("pong");  } else if (e.data === "pong") {    console.log("Received ping response from server.");  }});
socket.addEventListener("error", (e) => {  console.error(`Had error`, e);});