title: How to set up a Django URL regex that accepts only 3 specific words?
body: <p>I have my urls.py set up as follow right now:</p>
  
  <pre><code>urlpatterns = [
  url(r'^(?P&lt;content_type_name&gt;[a-zA-z-_]+)$', views.content_type, name = 'content_type'),
  ]
  </code></pre>
  
  <p>This makes it so that this url will accept any word or string of words separated by - or _ or both. However, I want a regex that will accept only one of three words for the content_type_name parameter - 'comics', 'articles', 'videos'.</p>
  
  <p>How do I set this up?</p>