如何使不一致机器人不区分大小写？discord.py

import discord
from discord.ext import commands

bot = commands.Bot(command_prefix='!')

@bot.event
async def on_message(message):
    content = message.content.lower()  # 将消息内容转换为小写
    # 处理不一致机器人的逻辑
    if content == 'hello':
        await message.channel.send('Hello!')
    elif content == 'bye':
        await message.channel.send('Goodbye!')
    # 其他指令和逻辑...

bot.run('YOUR_BOT_TOKEN')