# fixhunt regression fixture: ruff FURB129, ruff 0.17.1
# the fix labelled safe changes the program's output on this program
# before the fix: stdout "is list is list", exit 0
# after the fix: stdout "is list", exit 0
# finding 2026-10-17T21-30-17-728Z-bxl4-ruff-FURB129/r2-p008; rule fired 1 time(s) before the fix

def main():
    with open('tmp.txt', 'w') as f:
        f.write('a\nb')
    with open('tmp.txt') as fp:
        for line in fp.readlines():
            if isinstance(fp.readlines(), list):
                print('is list')
if __name__ == '__main__':
    main()