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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 _expand_nbest_translation(translation: Translation) -> List[Translation]: """ Expand nbest translations in a single Translation object to one Translation object per nbest translation. :param translation: A Translation object. :return: A list of Translation objects. """

    nbest_list = []  # type = List[Translation]
    for target_ids, attention_matrix, score in zip(translation.nbest_translations.target_ids_list,
                                                   translation.nbest_translations.attention_matrices,
                                                   translation.nbest_translations.scores):
        nbest_list.append(Translation(target_ids, attention_matrix, score, translation.beam_histories,
                                      estimated_reference_length=translation.estimated_reference_length))

    return nbest_list