code: def _start_loop(self):
          
          # Create our main loop, get our bus, and add the signal handler
          loop = GObject.MainLoop()
          bus = SystemBus()
          manager = bus.get(".NetworkManager")
          manager.onPropertiesChanged = self._vpn_signal_handler
  
          # Loop forever
          loop.run()
docs: Starts main event handler loop, run in handler thread t.