Python Bytes 50

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Brian #1: Think Like a Pythonista

• 2017, by @standupdev Luciano Ramalho
• The PyBay2017 playlist
• Covered in “Think Lika a Pythonista”
  • Creating a container type, a Deck of Cards.
  • Luciano shows how to utilize duck typing, builtin types, and operator overloading while creating a type without inheritance.
  • Uses a Jupyter notebook to work with the code.
  • Describes and shows monkeypatching to implement shuffle.
  • Watch until the end, he takes feedback from the audience to optimize some code.

Michael #2: Serpent.AI - Game Agent Framework

• Turn ANY video game in a sandbox environment for AI & Bot programming with Python.
• goal with Serpent.AI is to lower the barriers to entry when it comes to using games as sandboxes for code experiments.
• It unlocks your entire existing game library (Steam, DRM-Free etc.) to be used as potential game agent environments and it does so natively
• It also doesn't try to dictate how you solve your problems. Your game agent is your canvas!
• Even a twitch channel with live PyCharm + Jupyter + Game. Here’s a cool example: https://go.twitch.tv/videos/173580782
• Provides some useful conventions but is absolutely NOT opinionated about what you put in your agents:
  • Want to use the latest, cutting-edge deep reinforcement learning algorithm? ALLOWED.
  • Want to use computer vision techniques, image processing and trigonometry? ALLOWED.
  • Want to randomly press the Left or Right buttons? sigh ALLOWED.

Brian #3: MkDocs

• I’ve been creating pytest plugins using the pytest-plugin cookiecutter.
• One option is to start the documentation using mkdocs, so I thought I’d try it out.
• For the most part, you have a yaml file to configure things, and a directory with markdown files in it. Then you call mkdocs build and blammo, your documentation is built. I like markdown, so I’m going to try working with mkdocs more.
• Also want to try:
  • Generating documentation from source code using Christian Medina’s How to write your own Python documentation generator article and the code in a snippet, gendocs.py.
  • I know about Sphinx, but I’m not a fan of reStructured text.

Michael #4: PyInstaller 3.3 released

• PyInstaller is a program that freezes (packages) Python programs into stand-alone executables, under Windows, Linux, Mac OS X, FreeBSD, Solaris and AIX.
• The main goal of PyInstaller is to be compatible with 3rd-party packages out-of-the-box.
• Libraries like PyQt, Django or matplotlib are fully supported, without having to handle plugins or external data files manually.
• The #1 thing that stands out to me in this release: Python 3.6 support!
• PyInstaller can produce single immutable self contained dependency free portable exe files using the --one-file option.
• Consider the --noconsole option too
• cx_freeze vs pyinstaller? I can tell you that pyinstaller does a much better job of actually detecting and including dependencies. I recently tried both for freezing a multi-threaded, scipy based application and cx_freeze was a real hassle to get functional. Pyinstaller more or less just magically worked in my case whereas cx_freeze took hours of debugging.

Brian #5: PEX: A library and tool for generating .pex (Python EXecutable) files

• Developed by twitter. Originally part of the twitter.commons package.
• pex is a tool to create PEX files, which are “files are self-contained executable Python virtual environments.”, from pex.readthedocs.io.
• Python can import from zip files. You can add instructions at the beginning of a zip file to make it look like a python script. pex allows you to do that.
• Watch WTF is PEX?, a 16 min video describing how it works. Brian Wickman

Michael #6: Using Cython to protect a Python codebase

• A Python project that required the whole codebase to be protected
• They used Cython
• By following this guide, you should be able to cythonize a Python codebase with non-trivial package/module structure, thus making it difficult for evil hackers to reverse engineer it and steal your programming know-how.
• Although protecting Python sources from reverse engineering seems like a futile task at first, cythonizing all the code leads to a reasonable amount of security
• This was a Flask project!
• The current standard for Python archives is the wheel format (.whl), which aims to replace the .egg format. So, let's try to create a wheel with python setup.py bdist_wheel!
• Apparently, the archive contains not only compiled code, but also the sources.
• There is a way to fix this, however it is counter-intuitive.

Our news

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