title: Discord.py: MissingRequiredArgument: self is a required argument that is missing
body: <p>I want to change the presence when a user executes a command.
  I have the Discord bot in an own Class. To change the presence I need the self argument.
  But when I write</p>
  <pre class="lang-py prettyprint-override"><code>    @bot.command()
      async def change(self, ctx):
          await self.client.change_presence(activity=discord.Game(&quot;P-Hub&quot;))
  </code></pre>
  <p>I get the Error:</p>
  <pre><code>discord.ext.commands.errors.MissingRequiredArgument: ctx is a required argument that is missing.
  </code></pre>
  <p>And when I write:</p>
  <pre class="lang-py prettyprint-override"><code>    @bot.command()
      async def change(ctx, self):
          await self.client.change_presence(activity=discord.Game(&quot;P-Hub&quot;))
  </code></pre>
  <p>I get this error:</p>
  <pre><code>discord.ext.commands.errors.MissingRequiredArgument: self is a required argument that is missing.
  </code></pre>
  <p>The whole code is:</p>
  <pre class="lang-py prettyprint-override"><code>    class DiscordBot():
          def __init__(self, client, token):
              self.client = client
              self.token = token
  
          def run(self):
              self.client.run(self.token)
  
         @bot.command()
              async def change(ctx, self):
                  await self.client.change_presence(activity=discord.Game(&quot;P-Hub&quot;))
  
         @bot.event
             async def on_ready():
             print(&quot;My Ready is Body&quot;)
  
         @bot.listen()
             async def on_message(message):
                 print(str(message.author) + &quot;: &quot; + message.content)
  
         if __name__ == '__main__':
             client = DiscordBot(bot, 'token')
             client.run()
  </code></pre>
  <p>Does anyone have a solution?</p>