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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 csv_print(classes, class_stat, digit=5, class_param=None):
 """ Return csv file data. :param classes: classes list :type classes:list :param class_stat: statistic result for each class :type class_stat:dict :param digit: scale (the number of digits to the right of the decimal point in a number.) :type digit : int :param class_param : class parameters list for print, Example : ["TPR","TNR","AUC"] :type class_param : list :return: csv file data as str """

    result = "Class"
    classes.sort()
    for item in classes:
        result += ',"' + str(item) + '"'
    result += "\n"
    class_stat_keys = sorted(class_stat.keys())
    if isinstance(class_param, list):
        if set(class_param) <= set(class_stat_keys):
            class_stat_keys = class_param
    if len(class_stat_keys) < 1 or len(classes) < 1:
        return ""
    for key in class_stat_keys:
        row = [rounder(class_stat[key][i], digit) for i in classes]
        result += key + "," + ",".join(row)
        result += "\n"
    return result