#251: A 95% complete episode (wait for it)

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Special guest: Brett Cannon

Michael #1: auto-optional

• by Daan Luttik
• Did you know that concrete types cannot be None in Python typing?
• This is wrong:

      def do_a_thing(extra_info: str = None): ...
  

• auto-optional will fix it:

      def do_a_thing(extra_info: Optional[str] = None): ...
  

• Why would you want this?
• Easily modify external libraries that didn't pay attention to proper use of optional to improve mypy linting.
• Force consistency in your own code-base: Enforcing that None parameter implies an Optional type.
• Run via the CLI: auto-optional [path]

Brian #2: Making World-Class Docs Takes Effort

• Daniel Stenberg
• Six requirements for a project to get a gold star
  • docs in the code repo
  • NOT extracted from the code
  • examples, lots of examples, more than you think you need
  • document every API call you provide
  • easily accessible and browsable
  • and hopefully offline readable as well
  • easy to contribute to
• Non-stop iterating is key to having good docs.
• extra goodness
  • consistency for section titles
  • cross-references
• I’d add
  • Check for grammar and spelling mistakes
  • Consistency in all things, formatting, style, tone, depth of info of diff topics
  • Don’t be afraid to have a personality. docs that include easter eggs, fun examples, tasteful jokes, etc are nice, as long as that fun stuff doesn’t complicate the docs.
  • Don’t slam projects for having bad docs. Not all open source projects exist for your benefit.
    • You can make them better by contributing. :)

Brett #3: Starship

• Continuing the trend of stuff to help make your coding better, Python or not. 😉
• Also to make Michael’s new love of nerd fonts more useful. 😁
• And more Rust on this show as Paul Everitt says I must do. 😉
• Gives you a common shell prompt no matter which shell you use; I also find it easy to set up compared to most shells for their prompts
• Lots of integrated support for various developer things such as printing what Python version you have when the directory has a pyproject.toml file.
• Works nicely with the Python Launcher (as I mentioned the last time I was on).
• Has some pyenv support that I don’t use. 😁

Michael #4: JMESPath

• via Josh Thurston
• Spent tons of time figuring out how to parse the pretty print results that had layers of nested dictionaries and lists. This module saved me time in a big way.
• JMESPath (pronounced “james path”) allows you to declaratively specify how to extract elements from a JSON document.
• For example, given this document:

      {"foo": {"bar": "baz"}}
  

• The jmespath expression foo.bar will return “baz”.
• Even works with a projection-like result:

      {"foo": {"bar": [{"name": "one"}, {"name": "two"}]}}
  

• The expression: foo.bar[*].name will return ["one", "two"].
• Negative indexing is also supported (-1 refers to the last element in the list).
• Given the data above, the expression foo.bar[-1].name will return "two".

Brian #5: pedalboard - audio effects library

• from Spotify
• The “power, speed, and sound quality of a DAW”, but in Python.
• Introduction Article (warning: weird color changing header image that is painful to look at, so scroll past that quickly)
  • Built-in support for a number of basic audio transformations:
  • Convolution, Compressor, Chorus, Distortion
  • Gain, HighpassFilter, LadderFilter, Limiter, LowpassFilter
  • Phaser, Reverb

Brett #6: PEP 665 (and the journey so far)

• Attempt to standardize lock files for Python.
• Spent six months talking w/ folks privately to come up with the first public draft.
• Initially a strict lock file, but Poetry and PDM feedback was platform-agnostic was important.
• Proposal morphed to cover that.
• Took it public and led to over 150 comments on Discourse.
• People disliked it: from the title to the explanation to the proposed problem space to the actual solution.
• Gone back to the drawing board privately w/ one of the original objectors participating; looking like we are reaching a good consensus on how to frame things and how it should ultimately look.
• (Packaging) PEPs are hard.

Extras

Brian

• Python is popular, apparently, and “on the verge of another big step forward” (another good place for dun, dun, duuunnn, ?)
  • "It only needs to bridge 0.16% to surpass C. This might happen any time now. If Python becomes number 1, a new milestone has been reached in the TIOBE index. Only 2 other languages have ever been leading the pack so far, i.e. C and Java."

Michael

• Nerd Fonts
• Evrone interview with me
• Henry Schreiner’s Fish setup
• Aliases rather than CLI/venvs

Brett

• Will McGugan did a webinar w/ Paul Everitt about Textual (because it’s not a Python Bytes episode if Will’s name is not brought up).
• Python Launcher officially launched! (Last covered 30 episodes ago.)
  • Available in AUR, Fedora, and Homeberw (both macOS and Linux).
  • No reported bugs since launch!
• Still doing my syntactic sugar blog posts.
• The Python extension for VS Code has a refreshed testing UX; we’re coming for you, Brian. 😉

Joke: Last 5%