old_contents: /*eslint-env node:true, node*/
  
  var express = require('express');
  var app = express();
  
  app.use('/', express.static(__dirname + "/public"));
  
  var port = process.env.PORT | process.env.VCAP_APP_PORT || 5000;
  
  app.listen(port);
new_contents: /*eslint-env node:true, node*/
  
  var express = require('express');
  var app = express();
  
  app.use('/', express.static(__dirname + "/public"));
  
  var port = process.env.PORT | process.env.VCAP_APP_PORT || 4000;
  
  app.listen(port);
  
subject: change port