widget for accelerator group connections
with gtkAccelGroupConnectByPath or gtkAccelGroupConnect.
The closures can be used to monitor accelerator changes on widget,
by connecting to the GtkAccelGroup::accel-changed signal of the
GtkAccelGroup of a closure which can be found out with
gtkAccelGroupFromAccelClosure.gtkWidgetListAccelClosures(object)objectlist of closures