如何提取 discord.py 消息的内容

我正在尝试制作一个可以玩井字游戏的机器人。无法从中获取消息内容mes。例如：

@bot.event
async def on_message(mes):
print(int(mes))  # Вызывает ошибку
await bot.process_commands(mes)

完整游戏代码：

@bot.command()
async def play(ctx):
    board = Board()
    bot_turn = 'O'
    game_bot = Bot(True, 'O')

    await ctx.send(board)
    await ctx.send('[X]: Enter cell number')

    @bot.event
    async def on_message(mes):
        print(mes)
        edited = board.edit(mes, 'X')  # Здесь (на месте mes) должно быть содержимое сообщения игрока
        await ctx.send(board)

        if edited:
            while True:
                cell = game_bot.get_cell(board.get_board(), board.get_void())
                bot_edited = board.edit(cell, bot_turn)
                if bot_edited:
                    break

        winner = board.is_win()

        if winner != False:
            if winner == 'O':
                statistic['bot win'] += 1
            elif winner == 'X':
                statistic['player win'] += 1

            statistic['total games'] += 1
            save_stats(statistic)
            await ctx.send(f'[^^]: winner is {winner}')
            await bot.process_commands(mes)

        if board.is_fill():
            statistic['draw'] += 1
            statistic['total games'] += 1
            save_stats(statistic)
            await ctx.send('[^^]: Draw')
            await bot.process_commands(mes)