title: django many-to-many compare
body: <p>Is any way to compare two ManyToMany relationship from a different models?</p>
  
  <p>I have a model Days in common and with this other two models:</p>
  
  <ul>
  <li>Ticket (The Ticket has a m2m relation with Days)</li>
  <li>Check (The check has a m2m relation with Days)</li>
  </ul>
  
  <p>I can do it with two for what don't look really pretty or readable.</p>