qod json field to .txt file

JSONfieldtotxt.js

var filename = 'file.json';
var fs = require('fs');
var underscore = require('underscore');
var data = fs.readFileSync(filename).toString();
data = JSON.parse(data);
data = underscore.map(data,function(d){
  //change this
  return d.field;
});
data = underscore.uniq(data);
fs.writeFile('file.txt',data);