func (v *TreeModel) IterPrevious(iter *TreeIter) bool {
	c := C.gtk_tree_model_iter_previous(v.native(), iter.native())
	return gobool(c)
}
func (v *TreeModel) IterPrevious(iter *TreeIter) bool {
	c := C.gtk_tree_model_iter_previous(v.native(), iter.native())
	return gobool(c)
}
// IterPrevious is a wrapper around gtk_tree_model_iter_previous().