checkpyc.py

#!/usr/bin/env python3

import os
import sys
import time
import struct
import marshal
import binascii
import dis
import platform


def view_pyc_file(path):
    """Read and display a content of the Python`s bytecode in a pyc-file."""
    with open(path, 'rb') as file:
        magic = file.read(4)
        bit_field = None
        timestamp = None
        hashstr = None
        size = None
        if sys.version_info.major == 3 and sys.version_info.minor >= 7:
            bit_field = int.from_bytes(file.read(4), byteorder=sys.byteorder)
            if 1 & bit_field == 1:
                hashstr = file.read(8)
            else:
                timestamp = file.read(4)
                size = file.read(4)
                size = struct.unpack('I', size)[0]
        elif sys.version_info.major == 3 and sys.version_info.minor >= 3:
            timestamp = file.read(4)
            size = file.read(4)
            size = struct.unpack('I', size)[0]
        else:
            timestamp = file.read(4)

        code = marshal.load(file)

    magic = binascii.hexlify(magic).decode('utf-8')
    timestamp = time.asctime(time.localtime(struct.unpack('I', timestamp)[0]))

    #dis.disassemble(code)

    print('-' * 80)
    print(
        'Python version: {}\nMagic code: {}\nTimestamp: {}\nSize: {}\nHash: {}\nBitfield: {}'
        .format(platform.python_version(), magic, timestamp, size, hashstr, bit_field)
    )


if __name__ == '__main__':
    usage = 'Usage: checkpyc.py file.pyc'
    if len(sys.argv) <= 1 or not os.path.isfile(sys.argv[1]):
        print(usage)
        sys.exit()

    view_pyc_file(sys.argv[1])