code: def _load_screen_settings(self):
          
          # display number / use primary display
          combo = self.get_widget('display_n')
          dest_screen = self.settings.general.get_int('display-n')
          # If Guake is configured to use a screen that is not currently attached,
          # default to 'primary display' option.
          screen = self.get_widget('config-window').get_screen()
          n_screens = screen.get_n_monitors()
          if dest_screen > n_screens - 1:
              self.settings.general.set_boolean('mouse-display', False)
              dest_screen = screen.get_primary_monitor()
              self.settings.general.set_int('display-n', dest_screen)
  
          if dest_screen == ALWAYS_ON_PRIMARY:
              first_item = combo.get_model().get_iter_first()
              combo.set_active_iter(first_item)
          else:
              seen_first = False  # first item "always on primary" is special
              for i in combo.get_model():
                  if seen_first:
                      i_int = int(i[0].split()[0])  # extracts 1 from '1' or from '1 (primary)'
                      if i_int == dest_screen:
                          combo.set_active_iter(i.iter)
                  else:
                      seen_first = True
docs: Load screen settings