text: var fs = require('fs');
  var express = require('express');
  var app = express();
  
  app.get('/books', function(req, res){
    fs.readFile(process.argv[3], 'utf8', function(err, data){
      if (err){
        return res.sendStatus(500)
      }
  
      try {
        books = JSON.parse(data)
      } catch (err) {
        res.sendStatus(500)
      }
      res.json(books)
    });
  });
  
  app.listen(process.argv[2]);