title: Issues with Discord.py Async - Welcome Leave Messages
body: <p>So I currently have my own music bot that I coded using Discord.py. However, I am trying to add the on_member_join() and on_member_remove() methods, so that I can be notified using my own custom messages when someone leaves and joins(Discord's built in feature is fine, but it doesn't work when someone leaves, hence why I'm doing this)</p>
  <p>So I have a channel called welcome-leave on my server, which is where I want those welcome/leave messages to be printed by the bot. However, I'm not sure how to go about doing that.</p>
  <pre><code>@bot.event
  async def on_member_join(member):
      server = member.server.default_channel
      fmt = 'Welcome to the {1.name} Discord server, {0.mention}, please read the 
      rules and enjoy your stay.'
      await bot.send_message(server, fmt.format(member, member.server))
  
  @bot.event
  async def on_member_remove(member):
      server = member.server.default_channel
      fmt = '{0.mention} has left/been kicked from the server.'
      await bot.send_message(server, fmt.format(member, member.server))
  </code></pre>
  <p>This is currently my setup, but obviously it doesn't work. The error I get is that the Destination must either be Channel, PrivateChannel, User, or Object.</p>
  <p>I don't really have any idea on how to make my bot print these messages to that specific channel on my server. Any help would be really appreciated.</p>