如何使用response.write中的数据

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  res.write('Hello, ');
  res.write('World!');
  res.end(); // 结束响应
});

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

from flask import Flask, Response

app = Flask(__name__)

@app.route('/')
def hello_world():
    response = Response()
    response.write('Hello, ')
    response.write('World!')
    return response

if __name__ == '__main__':
    app.run(port=3000)

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloWorldServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.getWriter().write("Hello, ");
        response.getWriter().write("World!");
    }
}