A self-checking python quine, of sorts

quine.py

#!/usr/bin/env python3
'''
A "self-verifying" quine - `<quine> <source_file>` will only print itself
if `<quine>` has the same output as `cat <source_file>`
'''
source = r'''{foreword}

import sys, subprocess
if len(sys.argv) > 1:

    with open(sys.argv[1], 'rb') as f:
        quine = f.read()

    output = subprocess.check_output("%s %s" % (sys.executable, sys.argv[1]))
    if quine != output:
        sys.exit(1)

foreword = """#!/usr/bin/env python3
\'\'\'
A "self-verifying" quine - `<quine> <source_file>` will only print itself
if `<quine>` has the same output as `cat <source_file>`
\'\'\'
source = r\'\'\'"""
last_line = 'source.format(foreword=foreword + source + "\'\'\'", program=last_line)'
sys.stdout.write({program})
'''

import sys, subprocess
if len(sys.argv) > 1:

    with open(sys.argv[1], 'rb') as f:
        quine = f.read()

    output = subprocess.check_output("%s %s" % (sys.executable, sys.argv[1]))
    if quine != output:
        sys.exit(1)

foreword = """#!/usr/bin/env python3
\'\'\'
A "self-verifying" quine - `<quine> <source_file>` will only print itself
if `<quine>` has the same output as `cat <source_file>`
\'\'\'
source = r\'\'\'"""
last_line = 'source.format(foreword=foreword + source + "\'\'\'", program=last_line)'
sys.stdout.write(source.format(foreword=foreword + source + "'''", program=last_line))