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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 overall_jaccard_index_calc(jaccard_list):
 """ Calculate overall jaccard index. :param jaccard_list : list of jaccard index for each class :type jaccard_list : list :return: (jaccard_sum , jaccard_mean) as tuple """

    try:
        jaccard_sum = sum(jaccard_list)
        jaccard_mean = jaccard_sum / len(jaccard_list)
        return (jaccard_sum, jaccard_mean)
    except Exception:
        return "None"