title: Python GTK3 inheritance
body: <p>How can I inherit a GTK+3 class in python ? I'm trying to create a inherited class of Gtk.Application and what I got is a segfault.</p>
  
  <p>I've tried a lot of things, but with this I got a segfault:</p>
  
  <pre><code>class Program(Gtk.Application):
      def __init__(self):
          super().__init__(self)
  
  ...
  prg = Program.new("app_id", flags)
  </code></pre>