def METHOD_NAME(refs):
    print('ref pairwise BLEU: %.2f' % pairwise(refs))
    refs = list(zip(*refs))
    m = len(refs)
    concat_h = []
    concat_rest = [[] for j in range(m - 1)]
    for i, h in enumerate(refs):
        rest = refs[:i] + refs[i+1:]
        concat_h.append(h)
        for j in range(m - 1):
            concat_rest[j].extend(rest[j])
    concat_h = list(chain.from_iterable(concat_h))
    bleu = corpus_bleu(concat_h, concat_rest)
    print('multi-reference BLEU (leave-one-out): %.2f' % bleu)