如何使用discord.py在音乐机器人上获得最好的音频质量？

import discord
from discord.ext import commands

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

# 安装FFmpeg
# Windows用户可以从 https://ffmpeg.org/download.html 下载预编译的二进制文件，并将其添加到系统路径中
# Linux用户可以使用包管理器安装FFmpeg，例如：sudo apt-get install ffmpeg

# 安装libopus
# Windows用户可以从 https://opus-codec.org/downloads/ 下载预编译的二进制文件，并将其添加到系统路径中
# Linux用户可以使用包管理器安装libopus，例如：sudo apt-get install libopus-dev

import discord
from discord.ext import commands

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

@bot.command()
async def play(ctx, url):
    voice_channel = ctx.author.voice.channel
    voice_client = await voice_channel.connect()

    # 创建音频处理器
    ffmpeg_options = {
        'options': '-vn',
        'before_options': '-reconnect 1 -reconnect_streamed 1 -reconnect_delay_max 5'
    }
    ytdl_options = {
        'format': 'bestaudio/best',
        'postprocessors': [{
            'key': 'FFmpegExtractAudio',
            'preferredcodec': 'mp3',
            'preferredquality': '192',
        }],
    }
    ytdl = discord.utils.get(bot.voice_clients, guild=ctx.guild)
    if not ytdl.is_playing():
        with youtube_dl.YoutubeDL(ytdl_options) as ydl:
            info = ydl.extract_info(url, download=False)
            url2 = info['formats'][0]['url']
            voice_client.play(discord.FFmpegPCMAudio(url2, **ffmpeg_options))
            ytdl.is_playing()

bot.run('YOUR_BOT_TOKEN')