title: Using discord.py on linux I get the error 'Bot' object has no attribute 'join_voice_channel'
body: <p>Code in question:</p>
  
  <pre><code>bot = commands.Bot(command_prefix='!')
  @bot.command(pass_context=True)
      async def yt(ctx, url):
      author = ctx.message.author
      voice_channel = author.voice.channel
      vc = await bot.join_voice_channel(voice_channel)
  
      player = await vc.create_ytdl_player(url, before_options="-reconnect 1 -reconnect_streamed 1 -reconnect_delay_max 5")
      player.start()
  </code></pre>
  
  <p>Error I receive:</p>
  
  <pre><code>Traceback (most recent call last):
      File "/home/wilkins30/.local/lib/python3.7/site-packages/discord/ext/commands/core.py", line 79, in wrapped
          ret = await coro(*args, **kwargs)
      File "OverBot.py", line 286, in one
          vc = await bot.join_voice_channel(voice_channel)
  AttributeError: 'Bot' object has no attribute 'join_voice_channel'
  
  The above exception was the direct cause of the following exception:
  
  Traceback (most recent call last):
      File "/home/wilkins30/.local/lib/python3.7/site-packages/discord/ext/commands/bot.py", line 863, in invoke
          await ctx.command.invoke(ctx)
      File "/home/wilkins30/.local/lib/python3.7/site-packages/discord/ext/commands/core.py", line 727, in invoke
          await injected(*ctx.args, **ctx.kwargs)
      File "/home/wilkins30/.local/lib/python3.7/site-packages/discord/ext/commands/core.py", line 88, in wrapped
          raise CommandInvokeError(exc) from exc
  discord.ext.commands.errors.CommandInvokeError: Command raised an exception: 
  AttributeError: 'Bot' object has no attribute 'join_voice_channel'
  </code></pre>
  
  <p>I am running python3 in Ubuntu 19 on a google virtual machine. So I have looked all over and could only find this <a href="https://github.com/Rapptz/discord.py/issues/1130" rel="nofollow noreferrer">thread </a>talking about the issue but solutions there didn't work. This worked for me in a windows environment. which lead me to believe it was opus not being loaded so I reinstalled that and verified that it was being successfully called. I have also created a fresh instance of the virtual machine to no avail as well. I'm sort of lost at the moment.</p>