title: Control tab focus (choose next element to focus) with GTK / PyGTK
body: <p>How can I force the <kbd>Tab</kbd> to focus the element I want, is it possible to give my software a list of elements to cycle focus ?</p>
  
  <p>I remember once using a property called <code>tabindex</code>, but I can't find it anymore.</p>
  
  <p>Maybe, preventing <kbd>Tab</kbd> to focus an element could also work ?</p>