const puppeteer = require('puppeteer');

(async () => {
  // launch a headless browser
  const browser = await puppeteer.launch();

  // open a new page
  const page = await browser.newPage();

  // set a custom user agent (replace it with your desired user agent)
  await page.setUserAgent('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36');

  // navigate to the target URL
  await page.goto('http://httpbin.org/user-agent');

  // get the HTML text content
  const htmlContent = await page.evaluate(() => document.body.textContent);

  // print the HTML content to the console
  console.log(htmlContent);

  // close the browser
  await browser.close();
})();