Ned, could you check the darwin osascript in turtledemo.__main__, lines 138-149 is current (both needed and correct)?

            subprocess.run(
                    [
                        'osascript',
                        '-e', 'tell application "System Events"',
                        '-e', 'set frontmost of the first process whose '
                              'unix id is {} to true'.format(os.getpid()),
                        '-e', 'end tell',
                    ],
                    stderr=subprocess.DEVNULL,
                    stdout=subprocess.DEVNULL,)

The one line could be an fstring now.