old_contents: var MongoClient = require('mongodb').MongoClient;
  var format = require('util').format;
  var MONGOHQ_URL = process.env['MONGOHQ_URL'];
  var ModelUtil = require('./ModelUtil.js');
  
  function PublicTL() {
      var self = this;
  }
  
  PublicTL.prototype.fetch = function(limit, callback) {
      var self = this;
      function selectAction(collection, closeCb) {
          collection.find().limit(limit).toArray(function(err, results) {
              closeCb(err, results);
          });
      }
  
      ModelUtil.doAction('public_tl', selectAction, function(err, results) {
          callback(err, results);
      });
  }
  
  
  module.exports = PublicTL;
  
  
new_contents: var MongoClient = require('mongodb').MongoClient;
  var format = require('util').format;
  var MONGOHQ_URL = process.env['MONGOHQ_URL'];
  var ModelUtil = require('./ModelUtil.js');
  
  /**
   *  This model represents all public timeline
   *  posted by each users
   *
   */
  function PublicTL() {
      var self = this;
  }
  
  /**
   *  Get public timeline
   *
   *  @param limit
   */
  PublicTL.prototype.fetch = function(limit, callback) {
      var self = this;
      function selectAction(collection, closeCb) {
          collection.find().limit(limit).toArray(function(err, results) {
              closeCb(err, results);
          });
      }
  
      ModelUtil.doAction('public_tl', selectAction, function(err, results) {
          callback(err, results);
      });
  }
  
  
  module.exports = PublicTL;
  
  
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