code: function (newValue) {
                      // and no inheritance is involved
                      if (this === self) {
                        // notify the method but ...
                        var value = oldValue;
                        updateValue(newValue);
                        // ... do not update the get value
                        oldValue = value;
                      } else {
                        // with inheritance, simply set the property
                        // as if it was a regular assignment operation
                        setValue(this, prop, newValue);
                      }
                    }
docs: if not writable ...