title: Making a Legend/Key in GraphViz
body: <p>I’d like to include a legend or key in my GraphViz diagram. I’m having trouble figuring out what code to use, though. I also want to put it in a corner, but the only coord I know for sure is the bottom-left: <code>pos="10,10!"</code>.</p>
  
  <p>Does anyone know how I can get this to work?</p>