class GroupZipper {

    public GroupZipper up() {
        if (!canUp()) {
            throw new NoSuchElementException("Could not move up because this group does not have a parent");
        }

        this.index = parent.index;
        this.node = parent.node;
        this.parent = parent.parent;

        return this;
    }

    public  GroupZipper(KeePassFile keePassFile);
    private  GroupZipper(GroupZipper parent, Group group, int index);

}