title: Accessing the Object in the UpdateView to pass pk for success_url
body: <p>I want to the user to an view which takes an <code>pk</code> as argument.</p>
  
  <p>I want to use the <code>self.object</code> in the <code>UpdateView</code> to look up the <code>pk</code> and pass ist as <code>args</code> to the <code>lazy_reverse</code> at the  <code>success_url</code>.</p>
  
  <p>First of all, is there a better way to do it, and second, how do I access the Object?</p>