decompyle3

What decompyle3 is

decompyle3 turns Python bytecode into equivalent Python source and can also decompile fragments. The project says it accepts bytecode from Python 3.7 onward, with testing reported for Python 3.7 and 3.8. It focuses on bytecode rather than native-code decompilation. The command-line tool processes compiled `.pyc` and `.pyo` files and includes a `--syntax-verify` option. Installation is documented through PyPI with `pip install decompyle3` or from source. The software is free and open source under the GPL-3.0 license. Its stated boundaries include obfuscated code, Cython, MicroPython, and Py2EXE executables, which it does not handle directly. The project also cautions that decompilation has numerous bugs and that some long lists of expressions or statements can take a long time to process. Paid support is not offered as a regular service, and issue reports and their code are public, with no confidentiality.

Who it suits

It suits people seeking to recover Python source from supported bytecode, including fragment-level work. It may not fit projects involving obfuscated code, Cython, MicroPython, or Py2EXE executables.

Limits

The documented scope starts at Python 3.7 bytecode, with testing reported for 3.7 and 3.8. Obfuscated code, Cython, MicroPython, and Py2EXE executables are outside its direct handling, and decompilation may contain bugs or run slowly on long lists.

Getting started

1. Install Python package from PyPI with `pip install decompyle3`
2. Alternatively install decompyle3 from source
3. Run `decompyle3` on a compiled `.pyc` or `.pyo` file
4. Add `--syntax-verify` when you want syntax verification

Verdict

decompyle3 offers a free command-line route from Python bytecode to source, with documented support starting at version 3.7. Its stated limitations, accuracy cautions, and lack of confidential issue reporting are important considerations.