title: Is it possible to show a Boolean icon in the Django admin only if returned a boolean, else the actual return value?
body: <p>Yes, I know about <code>myfield.boolean = True</code>. What I am asking is, is it possible to do something like this:</p>
  
  <pre><code>def get_nominees(self, obj):
      return ", ".join([nominee.name for nominee in obj.nominees.all()]) \  # returns a string
          or False  # returns a False icon
  </code></pre>
  
  <p>When I attempt to do this with, e.g. <code>get_nominees.boolean = True</code>, I get a <code>KeyError</code>. </p>