def deduplicate_ground_truth_haplotypes(results):
    """
    Remove duplicate haplotype pairs

    :param results: list
        List of haplotype pairs from ground-truth enumeration
    """
    deduplicated = []
    prev = set()

    invert = lambda x: (x[1], x[0])

    for h, n1, n2 in results:
        if (h not in prev) and (invert(h) not in prev):
            deduplicated.append((h, n1, n2))
        
        prev.add(h)

    return deduplicated