Quick script checking if a given file may be a valid appimage file

poke-appimage.py

#!/usr/bin/env python3
import argparse
import struct


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument(
        'appimage', metavar='APPIMAGE', help="Appimage file to query",
        type=argparse.FileType(mode="rb"))
    ns = parser.parse_args()
    with ns.appimage as f:
        f.seek(8)
        tag = f.read(3)
    if tag == b'\x41\x49\x02':
        print("{} looks like a valid appimage file".format(f.name))
    else:
        print("{} doesn't look like a valid appimage file".format(f.name))


if __name__ == "__main__":
    main()