元组索引超出范围但我没有创建元组

有一个代码：

class Rubik:
    def __init__(self,Red=['r','r','r','r','r','r','r','r','r'],Blue=['b','b','b','b','b','b','b','b','b'],
                 Orange=['o','o','o','o','o','o','o','o','o'],Green=['g','g','g','g','g','g','g','g','g'],
                 White=['w','w','w','w','w','w','w','w','w'],Yellow=['y','y','y','y','y','y','y','y','y']):
        self.red = Red
        self.blue = Blue
        self.orange = Orange
        self.green = Green
        self.white = White
        self.yellow = Yellow

    def show_red(self):
        total = f"""{self.red[0]} {self.red[1]} {self.red[2]}\n
                   {self.red[3]} {self.red[4]} {self.red[5]}\n
                   {self.red[6]} {self.red[7]} {self.red[8]}"""
        return total

    def show_blue(self):
        total =  f"""{self.blue[0]} {self.blue[1]} {self.blue[2]}\n
                   {self.blue[3]} {self.blue[4]} {self.blue[5]}\n
                   {self.blue[6]} {self.blue[7]} {self.blue[8]}"""
        return total

    def show_orange(self):
        total = f"""{self.orange[0]} {self.orange[1]} {self.orange[2]}\n
                   {self.orange[3]} {self.orange[4]} {self.orange[5]}\n
                   {self.orange[6]} {self.orange[7]} {self.orange[8]}"""
        return total

    def show_green(self):
        total =  f"""{self.green[0]} {self.green[1]} {self.green[2]}\n
                     {self.green[3]} {self.green[4]} {self.green[5]}\n
                     {self.green[6]} {self.green[7]} {self.green[8]}"""
        return total

    def show_white(self):
        total =  f"""{self.white[0]} {self.white[1]} {self.white[2]}\n
                     {self.white[3]} {self.white[4]} {self.white[5]}\n
                     {self.white[6]} {self.white[7]} {self.white[8]}"""
        return total

    def show_yellow(self):
        total =  f"""{self.yellow[0]} {self.yellow[1]} {self.yellow[2]}\n
                     {self.yellow[3]} {self.yellow[4]} {self.yellow[5]}\n
                     {self.yellow[6]} {self.yellow[7]} {self.yellow[8]}"""
        return total

    def __str__(self):
        total = f"""
                {self.white[0]} {self.white[1]} {self.white[2]}
                {self.white[3]} {self.white[4]} {self.white[5]}
                {self.white[6]} {self.white[7]} {self.white[8]}\n
{self.red[0]} {self.red[1]} {self.red[2]}   {self.blue[0]} {self.blue[1]} {self.blue[2]}   \
{self.orange[0]} {self.orange[1]} {self.orange[2]}   {self.green[0]} {self.green[1]} {self.green[2]}
{self.red[3]} {self.red[4]} {self.red[5]}   {self.blue[3]} {self.blue[4]} {self.blue[5]}   \
{self.orange[3]} {self.orange[4]} {self.orange[5]}   {self.green[3]} {self.green[4]} {self.green[5]}
{self.red[6]} {self.red[7]} {self.red[8]}   {self.blue[6]} {self.blue[7]} {self.blue[8]}   \
{self.orange[6]} {self.orange[7]} {self.orange[8]}   {self.green[6]} {self.green[7]} {self.green[8]}\n
                {self.yellow[0]} {self.yellow[1]} {self.yellow[2]}
                {self.yellow[3]} {self.yellow[4]} {self.yellow[5]}
                {self.yellow[6]} {self.yellow[7]} {self.yellow[8]}"""
        return total

    def U(self, move=None):
        memory = [x for x in range(9)]
        red_list=['r','r','r','r','r','r','r','r','r']
        blue_list=['b','b','b','b','b','b','b','b','b']
        orange_list=['o','o','o','o','o','o','o','o','o']
        green_list=['g','g','g','g','g','g','g','g','g'],
        white_list=['w','w','w','w','w','w','w','w','w']
        yellow_list=['y','y','y','y','y','y','y','y','y']
        if move == None:
            memory[2] = 'w'
            memory[5] = 'w'
            memory[8] = 'w'

            white_list[2] = orange_list[2]
            white_list[5] = orange_list[5]
            white_list[8] = orange_list[8]

            orange_list[2] = yellow_list[2]
            orange_list[5] = yellow_list[5]
            orange_list[8] = yellow_list[8]

            yellow_list[2] = red_list[2]
            yellow_list[5] = red_list[5]
            yellow_list[8] = red_list[8]

            red_list[2] = memory[2]
            red_list[5] = memory[5]
            red_list[8] = memory[8]

        total = Rubik(red_list, blue_list, orange_list, green_list, white_list, yellow_list)
        return total


#==================================================================================================================================================
x = Rubik()
print(x.U())

出现异常：

IndexError
tuple index out of range
  File "C:\Users\User\Desktop\разработка\Проекты\проект rubiks_cube\rubiks_cube.py", line 57, in __str__
    {self.yellow[6]} {self.yellow[7]} {self.yellow[8]}"""
  File "C:\Users\User\Desktop\разработка\Проекты\проект rubiks_cube\rubiks_cube.py", line 95, in <module>
    print(x.U())

与元组相关的错误，虽然我没有创建元组......至少是故意的。值得注意的是，没有 U() 函数一切正常。请解释错误是什么以及如何解决。

或者，也许我错误地编写了init函数并且错误地输入了列表？

先感谢您。

Ps 试图“玩弄” str函数，或者更确切地说是总变量。出现线条时发生错误

{self.orange[0]} {self.orange[1]} {self.orange[2]}   {self.green[0]} {self.green[1]} {self.green[2]}