Çözüldü "AttributeError" hatası

import random


class ToplamaCikarma:
    def __init__(self, questions):
        self.questions = questions
        self.question_index = 0
        self.score = 0


    def getQuestion(self):
        return self.questions[self.question_index]


    def display_question(self):
        random_soru = random.choice(self.questions)
        question = random_soru["question"]
        choices = random_soru["choices"]
        print(question)
        for i, secenek in enumerate(choices, 1):
            print(f"{i}. {secenek[1]}")


    def guess(self, user_answer):
        question, options, answer = self.getQuestion()
        if user_answer == answer:
            self.score += 1
            print(f"Cevap doğru!")
        else:
            print("Maalesef cevap yanlış...")
        self.question_index += 1


soruCevapListesi = [
    { "title": "soru 1: toplama",
    "question": "2 + 3 = ?",
    "choices": [
        [1, "5"],
        [0, "4"],
        [0, "3"],
        [0, "2"]
    ]
    },
    { "title": "soru 2: çıkarma",
    "question": "38 - 4 = ?",
    "choices": [
        [1, "34"],
        [0, "35"],
        [0, "36"],
        [0, "37"]
    ]
    },
    {"title": "soru 3: toplama",
    "question": "15 + 3 = ?",
    "choices": [
        [0, "16"],
        [0, "17"],
        [1, "18"],
        [0, "9"]
    ]
    }
]


oyun = ToplamaCikarma(soruCevapListesi)
oyun.display_question()