return Objects.hashCode(part1, part2);
        }
    }

    private static class ThreePartDescribable extends AbstractDescribable {
        private final Object part1;
        private final Object part2;
        private final Object part3;

        ThreePartDescribable(Object part1, Object part2, Object part3) {
            this.part1 = part1;
            this.part2 = part2;