discord python bot “机器人未连接到语音通道。”

问：

import discord
from discord.ext import commands,tasks
import os
from dotenv import load_dotenv
import yt_dlp as youtube_dl

load_dotenv()
DISCORD_TOKEN = os.getenv("discord_token")
intents = discord.Intents().all()
client = discord.Client(intents=intents)
bot = commands.Bot(command_prefix='!',intents=intents)

youtube_dl.utils.bug_reports_message = lambda: ''
ytdl_format_options = {
    'format': 'bestaudio/best',
    'restrictfilenames': True,
    'noplaylist': True,
    'nocheckcertificate': True,
    'ignoreerrors': False,
    'logtostderr': False,
    'quiet': True,
    'no_warnings': True,
    'default_search': 'auto',
    'source_address': '0.0.0.0' 
}
ffmpeg_options = {
    'options': '-vn'
}
ytdl = youtube_dl.YoutubeDL(ytdl_format_options)
class YTDLSource(discord.PCMVolumeTransformer):
    def __init__(self, source, *, data, volume=0.5):
        super().__init__(source, volume)
        self.data = data
        self.title = data.get('title')
        self.url = ""
    @classmethod
    async def from_url(cls, url, *, loop=None, stream=False):
        loop = loop or asyncio.get_event_loop()
        data = await loop.run_in_executor(None, lambda: ytdl.extract_info(url, download=not stream))
        if 'entries' in data:
            # take first item from a playlist
            data = data['entries'][0]
            filename = data['title'] if stream else ytdl.prepare_filename(data)
            return filename

    @bot.command(name='join', help='Tells the bot to join the voice channel')
    async def join(ctx):
        if not ctx.message.author.voice:
            await ctx.send("{} is not connected to a voice channel".format(ctx.message.author.name))
            return
        else:
            channel = ctx.message.author.voice.channel
            await channel.connect()
    @bot.command(name='leave', help='To make the bot leave the voice channel')
    async def leave(ctx):
        voice_client = ctx.message.guild.voice_client
        if voice_client.is_connected():
            await voice_client.disconnect()
        else:
            await ctx.send("The bot is not connected to a voice channel.")

    @bot.command(name='play', help='To play song')
    async def play(ctx,url):
        try :
            server = ctx.message.guild
            voice_channel = server.voice_client
            async with ctx.typing():
                filename = await YTDLSource.from_url(url, loop=bot.loop)
                voice_channel.play(discord.FFmpegPCMAudio(executable="ffmpeg.exe", source=filename))
                await ctx.send('**Now playing:** {}'.format(filename))
        except:
            await ctx.send("The bot is not connected to a voice channel.")

if __name__ == "__main__" :
    bot.run(DISCORD_TOKEN)

我想在大学实习时为 discord 写一个音乐机器人。 我在 Windows 10 上运行了它，所有库都是新的。文件已上传到文件系统，但不会使用命令 ！play 在 Discord 中播放

更新了库，但没有帮助。 否则，机器人将按应有的方式工作。 我从 github 安装了最新版本的 yt_dlp，但没有帮助。还将 pip 包管理器更新到最新版本。