code: func (v *RadioMenuItem) GetGroup() (*glib.SList, error) {
  	c := C.gtk_radio_menu_item_get_group(v.native())
  	if c == nil {
  		return nil, nilPtrErr
  	}
  	return glib.WrapSList(uintptr(unsafe.Pointer(c))), nil
  }
docs: // GetGroup is a wrapper around gtk_radio_menu_item_get_group().