What will be the value of the Content-Type header sent to the client after running this code snippet?

What will be the value of the Content-Type header sent to the client after running this code snippet?

const http = require('http');
const server = http.createServer((req, res) => {
  res.setHeader('Content-Type', 'text/html');
  res.setHeader('Content-Type', 'application/json');
  res.end('{}');
});
server.listen(3000);