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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_rhymelists(stanza, scheme):
 """ Returns ordered lists of the stanza's word indices as defined by given scheme """

    rhymelists = defaultdict(list)
    for rhyme_group, word_index in zip(scheme, stanza.word_indices):
        rhymelists[rhyme_group].append(word_index)
    return list(rhymelists.values())