def get_label(index_name, df):
    """
    get the label by index the DataFrame
    :param index_name: string , the key for index from the processed filename
    :param df: DataFrame , with the column df['index'] created by get_csv_info(path)
    :return: string, the label ATTACK or NORMAL
    """
    label = df[df['index'] == index_name]['label'].values
    if len(label) == 0:  # mismatch will set as NULL
        label = 'NULL'
    else:
        label = label[0]
    if label != 'NULL':
        print(index_name, label)
    return label