title: Latency command in Discord.py
body: <p>I've looked in a lot of places and I can't find a way to make a ping (latency) command using <code>discord.py</code>, something like this:</p>
  
  <pre><code>@client.command(pass_context=True)
  async def pong(ctx):
      # Somehow find 'pingtime'
      await client.say(pingtime)
  </code></pre>