#248: while True: stand up, sit down

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• And Brian’s book too!

Special guest: Paul Everitt

Brian #1: Why I use attrs instead of pydantic

• Tin Tvrtković, @tintvrtkovic
• attrs vs dataclasses
  • Since dataclasses are a strict subset of attrs functionality. Recommend using attrs in most cases over dataclasses
  • attrs is faster, has more features, releases more frequently, offers over a wider range of Python versions.
• attrs vs Pydantic
  • attrs is a library for generating the boring parts of writing classes;
    • Pydantic is that but also
    • a complex validation library.
    • a structuring/unstructuring library, ex converting to json and back
  • attrs has opt-in validation that you have more control over
  • cattrs can be used for structuring/unstructuring
  • converters are opt-in for attrs, built into Pydantic, and can be wrong.
    • example using Pendulum that Pydantic mishandles
• Summary
  • attrs + cattrs + validators where necessary, converters where necessary
  • will be faster
  • you’ll have more control
  • Kind of a “small, sharp, specialized tools” vs “swiss army knife” comparison.

Michael #2: mclfy

• via __dann__
• Mcfly is an incredible Ctrl+r replacement
• McFly replaces your default ctrl-r shell history search with an intelligent search engine that takes into account your working directory and the context of recently executed commands.
• McFly's suggestions are prioritized in real time with a small neural network.
• Features
  • Rebinds ctrl-r to bring up a full-screen reverse history search prioritized with a small neural network.
  • Augments your shell history to track command exit status, timestamp, and execution directory in a SQLite database.
  • Maintains your normal shell history file as well so that you can stop using McFly whenever you want.
  • Includes a simple action to scrub any history item from the McFly database and your shell history files.
  • Designed to be extensible for other shells in the future.
  • Written in Rust, so it's fast and safe.

Paul #3: Textual and boilerplate removal

• In the race to make Textual the most talked-about package in Python Bytes history…
• I’d like to zoom in on a Twitter discussion he had about removing boilerplate
• I have traditionally been opposed to the convention-over-configuration approach that most successful Python projects have taken
• I dislike magic variable and file names, prefer explicit is better than implicit, actual symbols
• Lately, because of…tooling
• But Will’s approach to “boilerplate removal” is compelling, as it remains mypy friendly
• Still, I find it flawed…code meant to be read 2 years from now…that stuff that is implied-away, worries me
• Will is great at working-in-the-open, being a gentle, encouraging public figure

Brian #4: xdoctest

• “The xdoctest package is a re-write of Python's builtin doctest module. It replaces the old regex-based parser with a new abstract-syntax-tree based parser (using Python's ast module). The goal is to make doctests easier to write, simpler to configure, and encourage the pattern of test driven development.”
• “The main enhancements xdoctest offers over doctest are:
  1. All lines in the doctest can now be prefixed with >>>. Old-style doctests with ... are still valid.
  2. Additionally, the multi-line strings don't require any prefix (but its ok if they do have either prefix).
  3. Tests are executed in blocks, rather than line-by-line, thus comment-based directives (e.g. # doctest: +SKIP) are now applied to an entire block, rather than just a single line.
  4. Tests without a "want" statement will ignore any stdout / final evaluated value. This makes it easy to use simple assert statements to perform checks in code that might write to stdout.
  5. If your test has a "want" statement and ends with both a value and stdout, both are checked, and the test will pass if either matches.
  6. Output from multiple sequential print statements can now be checked by a single "got" statement. (new in 0.4.0).”
• Features I love
  • “The new got/want tester is very permissive by default; it ignores differences in whitespace”
  • You can make doctest normalize whitespace, but why should you have to?

Michael #5: Automate the standing desk with python

• via Joe Riedley, by David Kong
• “When I first started using it, I was very excited, but I quickly found myself sitting all day, in spite of the fancy desk.”
• I took off a few screws and … voila! A row of pins neatly exposed right in front.
• The pins in my control box, when connected correctly, simulate the pressing of the buttons on the front of the box.
• Raspberry Pi Zero, the simplest, most basic version. It doesn’t have all the bells and whistles, but it does everything I needed for this simple project, and it’s just $5(!).
• And the code

      from gpiozero import LED # The LED library allows easy pin control
      from time import sleep
      import randomrelay = LED(17) # I connected the relay to pin 17 and groundwhile True:
              relay.on()
              sleep(1)
              relay.off()
              sleep(random.randint(45, 60) * 60)
  

Paul #6: Hypermodern Python Cookiecutter

• I’ve been noodling with some code the last two years about bringing frontend DX to Python web dev
• Learning and talking more than adoption
• Running a modern Python project is a LOT of housekeeping
• Hypermodern Python Cookiecutter from Claudio Jolowicz teleported me to a state of the art I was looking for
• Poetry, Nox, GHA, pre-commit, flake8, PyPI uploads from CI, release drafter, Black, prettier, pytest, mypy, Sphinx and friends, GitHub labeler
• It’s NOT AT ALL just a cookiecutter
• The best part…it’s an enormously-detailed user guide, some blog posts with the “why”, it’s actively maintained
• The PR workflow is really well explained and wired up
• This could be…a course, a webinar
• Thanks Claudio

Extras

Michael:

• ActiveState's 2021 Software Supply Chain Security Survey
• Python 3.9.7 and 3.8.12 are now available
• From Shlomi Lanton, on your #2 Brian talked about having a history of all files to find the ones that were updated last, so I created granpa
• Also: wakepy now works correctly on macOS

Joke: Meaning