lru_cache 和清除缓存

有一个电报机器人根据时间表发送报价。添加到其lru_cache通过functools.

结果，用户收到了 3 次相同的报价（在不同的时间），尽管cache_clear()我在每次邮寄后都收到了。引号取自 MongoDB，这是我想要缓存的时刻，这样它就不会花一秒钟的时间。

class Quote:
    @lru_cache(maxsize=19)
    def check(self, user: str, check=True) -> dict:
        """Checks for quote available for {user}"""
        est_quotes = self.db.estimated_document_count()
        if self.db.count_documents({"Users": user}) >= est_quotes - 1:
            # removes user id from DB if there is no more available quotes for user
            self.db.update_many({"Users": user}, {"$pull": {"Users": user}})
        all_quotes = self.db.find({})
        while True:
            quote = all_quotes[random.randint(0, est_quotes - 1)]
            if not check:
                # if check for available is not required return random quote
                return quote
            if user in quote["Users"]:
                continue
            required_quote = quote
            self.db.update_one({"Quote": quote["Quote"]}, {"$push": {"Users": user}})
            return required_quote

    def random(self, user, checking=False):
        """ Sends random quote for user.
            If checking == False, it does not check for the presence of id in the database.
        """
        quo = self.check(user, check=checking)
        keyboard = types.InlineKeyboardMarkup()
        key_book = types.InlineKeyboardButton(text='📖', callback_data='book', url=quo["URL"])
        keyboard.add(key_book)
        #   key_like = types.InlineKeyboardButton(text='Нет', callback_data='no')
        #   keyboard.add(key_like)
        bot.send_message(user,
                         text=f'<i>{quo["Quote"]}\n</i>\n<b>{quo["Book"]}</b>\n#{quo["Author"]}',
                         parse_mode='HTML', reply_markup=keyboard)

    def randoms(self, group: int):
        """Sends random quote for users who aren't in 'stopped' list"""
        start_time = time.time()
        counter = 0
        with open(f'users{group}', 'r') as users_r:
            r = users_r.read().splitlines()
        print("=================================")
        for user_id in r:
            if user_id in self.stopped:
                continue
            try:
                self.random(str(user_id), True)
                print(f"Latency #{counter}: {str(time.time() - start_time)[:4]} seconds")
            except telebot.apihelper.ApiTelegramException as e:
                print(f"Bad ID ({user_id}):", e)
            except Exception as e:
                print(e)
            finally:
                counter += 1
        self.check.cache_clear()

很可能，我只是不太了解缓存的方式和内容，但我请您为我的问题提出最佳解决方案。