docs: def rename_selected_state(self, key_value, modifier_mask):
          """Callback method for shortcut action rename
  
          Searches for a single selected state model and open the according page. Page is created if it is not
          existing. Then the rename method of the state controller is called.
  
          :param key_value:
          :param modifier_mask:
          """
          selection = self.current_state_machine_m.selection
          if len(selection.states) == 1 and len(selection) == 1:
              selected_state = selection.get_selected_state()
              self.activate_state_tab(selected_state)
              _, state_identifier = self.find_page_of_state_m(selected_state)
              state_controller = self.tabs[state_identifier]['controller']
              state_controller.rename()