JavaScript file manipulation in OIC

Summary

Need to add carriage return/line at the end of the Jason file created through Stage activity

Content

Hi,

I need to add a carriage return/line at the end of the file and the file was created  under staging location (using stage activity). I try to use below java script function by passing the filename to  manipulate  but getting error at line ( const fs = require('fs'); ).

Do I need to import any java script file libraries?.  Please let me know.

function addEOL(filename) {

    const fs = require('fs');

    fs.appendFile(filename, 'data to append', function (err) {
      if (err) throw err;