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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 authors_titles_validator(record, result):
 """Compute a validation score for the possible match. The score is based on a similarity score of the authors sets and the maximum Jaccard index found between 2 titles: one from the record and one from the result title sets. If the computed score is higher than 0.5, then the match is valid, otherwise it is not. Args: record (dict):
 the given record we are trying to match with similar ones in INSPIRE. result (dict):
 possible match returned by the ES query that needs to be validated. Returns: bool: validation decision. """

    record_authors = get_value(record, 'authors', [])
    result_authors = get_value(result, '_source.authors', [])

    author_score = compute_author_match_score(record_authors, result_authors)

    title_max_score = 0.0
    record_titles = get_value(record, 'titles.title', [])
    result_titles = get_value(result, '_source.titles.title', [])

    for cartesian_pair in product(record_titles, result_titles):
        record_title_tokens = get_tokenized_title(cartesian_pair[0])
        result_title_tokens = get_tokenized_title(cartesian_pair[1])
        current_title_jaccard = compute_jaccard_index(record_title_tokens, result_title_tokens)

        if current_title_jaccard > title_max_score and current_title_jaccard >= 0.5:
            title_max_score = current_title_jaccard

    return (author_score + title_max_score) / 2 > 0.5