(student_scores, student_names)
:param student_scores: list of scores in descending order.
     :param student_names: list of names in descending order by exam score.
     :return: list of strings in format ["<rank>. <student name>: <score>"].
:param student_scores: list of scores in descending order.
     :param student_names: list of names in descending order by exam score.
     :return: list of strings in format ["<rank>. <student name>: <score>"].
: param student_scores : list of scores in descending order . : param student_names : list of names in descending order by exam score . : return : list of strings in format [ <rank > . <student name > : <score > ] .
def student_ranking(student_scores, student_names):
    """
     :param student_scores: list of scores in descending order.
     :param student_names: list of names in descending order by exam score.
     :return: list of strings in format ["<rank>. <student name>: <score>"].
     """

    pass
def student_ranking ( student_scores , student_names ) : pass