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#320: The Bug Is In The JavaScript

Published Tue, Jan 24, 2023, recorded Tue, Jan 24, 2023
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Brian #1: markdown-it-py

Michael #2: Sketch

  • via Jake Firman
  • Sketch is an AI code-writing assistant for pandas users that understands the context of your data
  • A Natural Language interface that successfully navigates many tasks in the data stack landscape.
    • Data Cataloging:
      • General tagging (eg. PII identification)
      • Metadata generation (names and descriptions)
    • Data Engineering:
      • Data cleaning and masking (compliance)
      • Derived feature creation and extraction
    • Data Analysis:
      • Data questions
      • Data visualization
  • Watch the video on the GitHub page for a quick intro

Brian #3: Fixing Circular Imports in Python with Protocol

  • Built on Subclassing in Python Redux from Hynek
    • We covered this in the summer of 2021, episode 240
    • However, I re-read it recently due to a typing problem
    • Problem is when an object passes itself to another module to be called later.
      • This is common in many design patterns, including just normal callback functions.
      • Normally not a problem with Python, due to duck typing.
      • But with type hints, suddenly it seems like both modules need types from the other.
    • So how do you have two modules use types from each other without a circular import.
    • Hynek produces two options
      • Abstract Data Types, aka Interfaces, using the abc module
        • Requires a third interface class
      • Structural subtyping with Protocol
        • This is what I think I’ll use more often and I’m kinda in love with it now that I understand it.
        • Still has a third type, but one of the modules doesn’t have to know about it.
      • "Structural Subtyping : Structural subtyping is duck typing for types: if your class fulfills the constraints of a [Protocol](, it’s automatically considered a subtype of it. Therefore, a class can implement many Protocols from all kinds of packages without knowing about them!”
  • The Fixing Circular Imports in Python with Protocol article walks through one example of two classes talking with each other, typing, circular imports, and fixing them with Protocol

Michael #4: unrepl

  • via/by Ruud van der Ham
  • We’ve seen the code samples:

        >>> board = []
    >>> for i in range(3):
    ...     row = ['_'] * 3
    ...     board.append(row)
    >>> board
    [['_', '_', '_'], ['_', '_', '_'], ['_', '_', '_']]
    >>> board\[2\][0] = 'X'  
    >>> board
    [['_', '_', '_'], ['_', '_', '_'], ['X', '_', '_']]
  • But you cannot really run this code. You can’t paste it into a REPL yourself nor can you put it into a .py file.

  • So you unrepl it: Copying the above code to the clipboard and run unrepl.
  • Paste the result and now you can.
  • Unrepl can be used as a command line tool but also as a module.
  • The REPL functionality of underscore (_) to get access to the last value is also supported.



  • You'll want to update your git ASAP.
  • Get course releases at Talk Python via RSS
  • Gist for using Turnstile with Python + Pydantic

Joke: there's a bug in the js

  • You’ve checked all your database indexes,
  • You’ve tuned all your API hooks,
  • You’re starting to think
  • That you might need a drink,
  • Because there’s only one place left to look:
  • There must be a bug in the javascript
  • Because everything else was built properly
  • But the frontend’s a pile of crap ;)

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