extension Extension<T extends num> on List<T> {
  external T field;
  external static int staticField;
  external final T finalField;
  external static final int staticFinalField;
  external T method();
  external static int staticMethod();
  external T get getter;
  external static int get staticGetter;
  external void set setter(T value);
  external static void set staticSetter(int value);
  external T get property;
  external void set property(T value);
  external static int get staticProperty;
  external static void set staticProperty(int value);
  external final T fieldSetter;
  external void set fieldSetter(T value);
  external static final int staticFieldSetter;
  external static void set staticFieldSetter(int value);
}

test() {}
main() {}