| Set ``__file__`` while running a startup file. Like Python, IDLE optionally | |
| runs one startup file in the Shell window before presenting the first interactive | |
| input prompt. For IDLE, ``-s`` runs a file named in environmental variable | |
| :envvar:`IDLESTARTUP` or :envvar:`PYTHONSTARTUP`; ``-r file`` runs | |
| ``file``. Python sets ``__file__`` to the startup file name before running the | |
| file and unsets it before the first prompt. IDLE now does the same when run | |
| normally, without the ``-n`` option. |