static Model of(BuildContext context) {
  _ModelBindingScope scope = context.inheritFromWidgetOfExactType(_ModelBindingScope);
  return scope.modelBindingState.currentModel;
}

static void update(BuildContext context, Model newModel) {
  _ModelBindingScope scope = context.inheritFromWidgetOfExactType(_ModelBindingScope);
  scope.modelBindingState.updateModel(newModel);
}