Discord.py通过对特定消息的反应来添加角色

Question

我已经想出了如何在频道中添加此功能，但是我希望它可以在特定消息上使用。有人可以帮我吗？

 @client.event
    async def on_reaction_add(reaction, user):
        channel = 'xxx'
        EuMessage_id = 'xxx'
        EuMsg = client.get_message(channel, EuMessage_id)
        roleEU = discord.utils.get(user.server.roles, name='EU')
        roleUS = discord.utils.get(user.server.roles, name='US')
        roleJP = discord.utils.get(user.server.roles, name='JP')

    #EU Role
        if reaction.message.channel.id != EuMsg:
            return #So it only happens in the specified channel
        if str(reaction.emoji) == "":
            print("Role EU added")
            await client.add_roles(user, roleEU)