code: function(key, callback) {
        if (key) {
          var _data = this.store.proxy.get(this.prefix + key),
              data;
          if ('undefined' !== typeof window) {
            // browser
            try {
              data = JSON.parse(_data);
            } catch (e) {
              data = _data;
            }
          } else {
            data = _data;
          }
          callback(null, data);
        } else {
          callback('missing key');
        }
      }
docs: Load stored item
  
  @param {String} key The key of the item
  @param {Function} callback Function called when the item is loaded
  @return {callback(err, data)} The callback to execute as result
  @param {String} callback.err Error if occurred
  @param {Object} callback.data The loaded item