text: var jsonfile = require('jsonfile')
  var file = 'wallpapers_info.json'
  // var file2 = 'wallpapers_info2.json'
  var newobj
  
  jsonfile.readFile(file, function(err, obj) {
    newobj = obj;
    newobj.forEach(function(f) {
      console.log(f.src.slice(0,14)+'thumbs'+f.src.slice(40,-4)+'_thumb'+f.src.slice(-4));
      thb = (f.src.slice(0,14)+'thumbs'+f.src.slice(40,-4)+'_thumb'+f.src.slice(-4));
      f.thb=thb;
    });
  
    // write the object 'newobj' to 'file' with correct spacing
    jsonfile.writeFile(file,newobj, {spaces: 2},function (err) {
      console.log(err);
    })
  });
  