https://qiita.com/nama40024/questions/bd1115a6a000e4d9982a#answer-cfc3f8d990f2e01d46e4

hitandblow.py

import random


class Answer:
    """出題者"""

    def __init__(self, digits: int) -> None:
        """digits桁の重複しない数を作って隠し持つ"""
        self._number = ''.join(map(str, random.sample(range(0, 10), digits)))

    def __str__(self) -> str:
        """表示用文字列を返す"""
        return self._number

    def __eq__(self, number: str) -> bool:
        """numberが正解ならTrue、違えばFalseを返す"""
        return number == self._number

    def judge(self, number: str) -> None:
        """numberのhit数,blow数を表示する"""
        hit = blow = 0
        for g, a in zip(number, self._number):
            if g == a:  # 同じ桁で同じ数
                hit += 1
            elif g in self._number:  # 違う桁で正解の中に数がある
                blow += 1
        print(f'{hit} HIT {blow} BLOW')


class Player:
    """回答者"""

    def guess_number(self, digits: int) -> str:
        """digits桁の重複しない数を推測する"""
        while True:
            number = input(f'{digits}桁の重複しない数を入力: ')
            if len(set(number)) == digits and number.isdigit():
                return number


class HitAndBlow:
    """数当てゲーム"""
    LIMIT = 10  # 回答制限回数

    def play(self, digits: int = 3) -> None:
        """digits桁の数当てゲームを遊ぶ"""
        answer = Answer(digits)
        player = Player()
        print('Hit and Blowを開始します')
        for limit in range(self.LIMIT, 0, -1):
            print(f'あと{limit}回')
            number = player.guess_number(digits)
            answer.judge(number)
            if number == answer:  # answer.__eq__(number)
                print(f'おめでとう！正解の数は{answer}だ！')  # answer.__str__()
                return
        print(f'おしい！正解の数字は{answer}')  # answer.__str__()


if __name__ == '__main__':
    HitAndBlow().play()