问是什么导致了AttributeError：“coroutine”对象没有属性“内容”？

EN

AttributeError: 'coroutine' object has no attribute 'content'
C:\Users\tuhin\AppData\Local\Programs\Python\Python310\lib\site-packages\discord\client.py:348: RuntimeWarning: coroutine 'wait_for' was never awaited
  await self.on_error(event_name, *args, **kwargs)
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

# bot.py
import os
import discord
from dotenv import load_dotenv
import random
from discord.ext import commands
load_dotenv()
PYTHONTRACEMALLOC = 1
TOKEN = "MTAwOTI1OTYxOTMwNDA5OTkwMQ.Gr-Cgn.L-m3iIIgWXkVvdGbdX3lWun9yetTOAuzIkbGI0"
client = discord.Client()
list = ['rock', 'paper', 'scissors']
@client.event
async def on_ready():
    print(f'{client.user.name} has connected to Discord!')

@client.event
async def on_member_join(member):
    member.create_dm()
    member.dm_channel.send(
        f'Hi {member.name}, welcome to my Discord server!'
    )
@client.event
async def on_message(message):
    if message.author.bot: return
    if message.content.lower() == "rps":
        await message.channel.send(message.author.mention + " started a game of rps")
        def is_correct(m):
            return m.author == message.author
            
        user_choice = (client.wait_for('message', check=is_correct)).content
        choices = random.choice(list)
        print(choices)
        if user_choice.lower() == choices:
            message.channel.send("Tie!")
        elif user_choice.lower() == "rock" and choices == "paper":
            message.channel.send("i win, i chose paper")
        elif user_choice.lower() == "rock" and choices == "scissors":
            message.channel.send("you win, i chose scissors")
        elif user_choice.lower() == "scissors" and choices == "paper":
            message.channel.send("you win, i chose paper")
        elif user_choice.lower() == "scissors" and choices == "rock":
            message.channel.send("i win, i chose rock")
        elif user_choice.lower() == "paper" and choices == "scissors":
            message.channel.send("i win, i chose scissors")
        elif user_choice.lower() == "paper" and choices == "rock":
            message.channel.send("you win, i chose rock")

     
    



client.run(TOKEN)