如何设置EIO版本？

const http = require('http');
const socketIo = require('socket.io');

const server = http.createServer();
const io = socketIo(server, {
  engine: {
    version: '4' // 设置EIO版本为4
  }
});

io.on('connection', (socket) => {
  console.log('A user connected');
  socket.on('disconnect', () => {
    console.log('User disconnected');
  });
});

server.listen(3000, () => {
  console.log('Server is running on port 3000');
});

const http = require('http');
const socketIo = require('socket.io');

const server = http.createServer();
const io = socketIo(server, {
  engine: {
    version: '3' // 设置EIO版本为3
  }
});

io.on('connection', (socket) => {
  console.log('A user connected');
  socket.on('disconnect', () => {
    console.log('User disconnected');
  });
});

server.listen(3000, () => {
  console.log('Server is running on port 3000');
});