def METHOD_NAME(self, cb: Gtk.ComboBox, callback: Callable[[Mapping], bool]):
    l_iter = cb.get_model().get_iter_first()
    while l_iter is not None:
        if callback(cb.get_model()[l_iter]):
            cb.set_active_iter(l_iter)
            return
        l_iter = cb.get_model().iter_next(l_iter)