def shake(self, force=False):
        "Prepare to shake the application's root window."
        if force:
            tkinter._tkinter.setbusywaitinterval(20)
        elif tkinter._tkinter.getbusywaitinterval() != 20:
            # Show error message if not running at 50 FPS.
            self.__error.show()
            self.operations_enabled = True
            return
        # Shake window at 50 FPS.
        self.after_idle(self.__shake)
Prepare to shake the application's root window.
recipes/Python/577632_Directory_Pruner_1/recipe-577632.py