@staticmethod
def select_best_candidate(candidates):
    """
        Selects the best calculate from a list by it's content_score.

        :param candidates: list of candidates to get the best one
        :return: best candidate
        """
    sorted_candidates = sorted(candidates.values(), key=lambda x: x[
        'content_score'], reverse=True)
    if len(sorted_candidates) == 0:
        return None
    best_candidate = sorted_candidates[0]
    return best_candidate
