Problem:
Write a program which reads $n$ dices constructed in the same way as [Dice I](description.jsp?id=ITP1_11_A), and determines whether they are all different. For the determination, use the same way as [Dice III](description.jsp?id=ITP1_11_C).

Incorrect submission (verdict: Wrong Answer):
class Dice:
    def __init__(self, init_values = ['1','2','3','4','5','6']):
        self.value = dict(zip(["top", "front","right","left","back","bottom"]\
                             , init_values))

    #north, south, east and west
    def roll(self, direction):
        if direction == 'N':
            self.value["top"], self.value["front"], self.value["bottom"], self.value["back"] = \
            self.value["front"], self.value["bottom"], self.value["back"], self.value["top"]
        elif direction == 'S':
            self.value["top"], self.value["back"], self.value["bottom"], self.value["front"] = \
            self.value["back"], self.value["bottom"], self.value["front"], self.value["top"]
        elif direction == 'E':
            self.value["top"], self.value["left"], self.value["bottom"], self.value["right"] = \
            self.value["left"], self.value["bottom"], self.value["right"], self.value["top"]
        elif direction == 'W':
            self.value["top"], self.value["right"], self.value["bottom"], self.value["left"] = \
            self.value["right"], self.value["bottom"], self.value["left"], self.value["top"]
        else:
            print("Error: illegal format.")

    # clockwise, counterclockwise
    def spin(self, direction):
        if direction == "CW":
            self.value["front"], self.value["right"], self.value["back"], self.value["left"] = \
            self.value["right"], self.value["back"], self.value["left"], self.value["front"]
        elif direction == "CCW":
            self.value["front"], self.value["left"], self.value["back"], self.value["right"] = \
            self.value["left"], self.value["back"], self.value["right"], self.value["front"]
        else:
            print("Error: illegal format.")

    def is_same(self, other_dice):
        for direction in 'SESESE':
            other_dice.roll(direction)
            if self.value["top"] == other_dice.value["top"]:
                for j in range(4):
                    other_dice.spin("CW")
                    if self.value == other_dice.value:
                        return True
        return False

n = int(input())
dice_arr = []
for i in range(n):
    dice_arr.append(Dice(input().split()))

result = "Yes"
for i in range(len(dice_arr)-1):
    for j in range(i+1,len(dice_arr)):
        if dice_arr[i].is_same(dice_arr[j]):
            result = "No"
            print(i, j, "\n", dice_arr[i].value, "\n", dice_arr[j].value)
            break
    if result == "No":
        break

print(result)

Fixed, accepted submission:
class Dice:
    def __init__(self, init_values = ['1','2','3','4','5','6']):
        self.value = dict(zip(["top", "front","right","left","back","bottom"]\
                             , init_values))

    #north, south, east and west
    def roll(self, direction):
        if direction == 'N':
            self.value["top"], self.value["front"], self.value["bottom"], self.value["back"] = \
            self.value["front"], self.value["bottom"], self.value["back"], self.value["top"]
        elif direction == 'S':
            self.value["top"], self.value["back"], self.value["bottom"], self.value["front"] = \
            self.value["back"], self.value["bottom"], self.value["front"], self.value["top"]
        elif direction == 'E':
            self.value["top"], self.value["left"], self.value["bottom"], self.value["right"] = \
            self.value["left"], self.value["bottom"], self.value["right"], self.value["top"]
        elif direction == 'W':
            self.value["top"], self.value["right"], self.value["bottom"], self.value["left"] = \
            self.value["right"], self.value["bottom"], self.value["left"], self.value["top"]
        else:
            print("Error: illegal format.")

    # clockwise, counterclockwise
    def spin(self, direction):
        if direction == "CW":
            self.value["front"], self.value["right"], self.value["back"], self.value["left"] = \
            self.value["right"], self.value["back"], self.value["left"], self.value["front"]
        elif direction == "CCW":
            self.value["front"], self.value["left"], self.value["back"], self.value["right"] = \
            self.value["left"], self.value["back"], self.value["right"], self.value["front"]
        else:
            print("Error: illegal format.")

    def is_same(self, other_dice):
        for direction in 'SESESE':
            other_dice.roll(direction)
            if self.value["top"] == other_dice.value["top"]:
                for j in range(4):
                    other_dice.spin("CW")
                    if self.value == other_dice.value:
                        return True
        return False

n = int(input())
dice_arr = []
for i in range(n):
    dice_arr.append(Dice(input().split()))

result = "Yes"
for i in range(len(dice_arr)-1):
    for j in range(i+1,len(dice_arr)):
        if dice_arr[i].is_same(dice_arr[j]):
            result = "No"
            break
    if result == "No":
        break

print(result)