docs: def on_mouse_click(self, widget, event):
          """state insertion on mouse click
  
          :param widget:
          :param Gdk.Event event: mouse click event
          """
          import rafcon.gui.helpers.state_machine as gui_helper_state_machine
          if self.view.get_path_at_pos(int(event.x), int(event.y)) is not None \
                  and len(self.view.get_selected_items()) > 0:
              return gui_helper_state_machine.insert_state_into_selected_state(self._get_state(), False)