code: function (key, value) {
                  var mappedKey = getMappedKey(key, true);
  
                  storage.setAttribute(mappedKey, value);
                  storage.save("JSONPersist");
              }
docs: Internal method to Add a key/value pair in the list.
  @param {String} key identifier of a value
  @param {String} value value to be stored after serialization