为什么节点中的fs在最后运行，即使它在Express.js中被声明为顶部

In my routes directory I have users.js and index.js. In my users.js file i have written a function to read files in my folder using ('fs').This function is written at the top but it always executes at the end. Can anyone help me out with it?In my routes directory I have users.js and inde