Python Detect Ubuntu Shutdown Signal

import signalimport timeis_shutdown = Falsedef stop(signum, frame):    global is_shutdown    is_shutdown = True    print('SIGTERM')signal.signal(signal.SIGTERM, stop)print('START')while not is_shutdown:    print('.', end='', flush=True)    time.sleep(1)print('END')

• SIGINT: Interrupt from keyboard (CTRL + C).
• SIGTERM: Termination signal.
• SIGHUP: Hangup detected on controlling terminal or death of controlling process.
• SIGKILL: Kill signal. It cannot be caught, blocked, or ignored.

NOTE: For systemd stop, you will receive SIGTERM followed by SIGHUP.

Reference:

• https://docs.python.org/3/library/signal.html