So I m kind of new to Open light speed, and i m just trying to set up a simple hello world express app which i did by replacing the Example app.js file, and it worked just fine, but then, i deleted the app.js file, and instead in the same containing folder, i used express generator to generate another app, which would normal print welcome to express, but it doesn't work, by question then is this, how do i locate the file or would i say the config file that starts the express app as in "node app.js"?