Nah. You only need the RPi Tools add-on, because it contains the Python GPIO library.
- Create the Python script inside of your /storage folder (e.g. /storage/scripts/gpio-reboot.py).
- Make it executable: chmod +x /storage/scripts/gpio-reboot.py
- Create /storage/.config/autostart.sh.
- Write the Python call into autostart.sh.: python /storage/scripts/gpio-reboot.py &
Then the script will run on every boot sequence.