old_contents: var Util = require("util");
  
  // TODO
  
new_contents: var Util = require("util");
  var API_URL = "https://www.googleapis.com/youtube/v3/";
  
  function createUrl (api, options) {
  
      var url = API_URL + api;
  
      options.access_token = (this.Client.getConfig().auth || {}).token;
  
      var i = -1;
      for (var opt in options) {
          var value = options[opt];
          url += (++i === 0 ? "?" : "&") + opt + "=" + value;
      }
  
      return url;
  }
  
  exports.createUrl = createUrl;
  
subject: add createUrl function in util