anti_decomp.py

from xdis.load import load_module
from xdis.code import Code2Compat
import uncompyle6
import xdis.main
import sys

if __name__ == "__main__":
    if len(sys.argv) <= 1:
        print("Usage: anti_decomp.py <some_py2_file.pyc>")
        sys.exit(1)

    filename = sys.argv[1]
    filename_base = filename.split('.')[0]

    (version, timestamp, magic_int, co, pypy, source_size) = load_module(filename)
    opc = xdis.main.get_opcode(version, pypy)

    co_code = bytearray(len(co.co_code))
    co_code[:] = co.co_code[:]

    co_code.append(0x9) # Add a NOP

    new_co = Code2Compat(
        co.co_argcount,
        co.co_nlocals,
        co.co_stacksize,
        co.co_flags,
        co_code,
        co.co_consts,
        co.co_names,
        co.co_varnames,
        co.co_filename,
        co.co_name,
        co.co_firstlineno,
        co.co_lnotab,
        co.co_freevars,
        co.co_cellvars,
    )

    # Crashes with: Parse error at or near `None' instruction at offset -1
    uncompyle6.main.decompile(version, new_co, sys.stdout)