Issue #749

Polars vs SQL, Constants, deque, and More

Aug. 25, 2026

Polars vs SQL, Constants, deque, and More
#749 – AUGUST 25, 2026 VIEW IN BROWSER
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The Polars vs SQL Differences Nobody Is Talking About
Some problems can be attacked with either SQL or Polars, but subtle differences in how the two mechanisms work can run you into trouble. Learn more about these potential gotchas.
MARCO GORELLI

Python’s Pre-Declared Constants Are Kinda Weird
Python has six built in constants and the behavior between them is rather inconsistent. This article shows you all six and why some of them are weird.
SEBSITE.PW

Type Checking Could Be the Guardrail Your Agent Is Missing
Coding agents write a lot of Python, and they write it fast. Having your agent call a type checker can prevent common type bugs creeping in. Pyrefly is an open-source type checker built in Rust that’s fast enough to keep up with your agent’s inference loop. Learn More
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Working With Python’s deque
Learn how to use Python’s deque to efficiently append and pop items from both ends, build queues and stacks, and set maxlen for bounded history.
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Quiz: Working With Python’s deque
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PEP 839: PyFrozenSetWriter and PyFrozenDictWriter C API (Draft)
PYTHON.ORG

PEP 842: Module Exports (Withdrawn)
PYTHON.ORG

Mojo Is Now Open Source!
MODULAR


Articles & Tutorials


Navigating Silent Failures in AI: Strategies for Effective Oversight
Why do AI systems silently fail? How can you set up a system that produces results while also reviewing and validating the work? This week on the show, Calvin Hendryx-Parker returns to discuss his recent talk “Orchestrate Agentic AI: Context, Checklists, and No-Miss Reviews.”
REAL PYTHON podcast

How AWS Powers PyPI and the PSF
The Python Software Foundation runs a fair amount of software, including the infrastructure behind PyPI, Python.org, PyCon US, and more. This article by the Director of Engineering at the PSF talks about how they do it and what tech gets used.
JACOB COFFEE

JavaScript in the Front, Python in the Back
Sean refers to the mixing of React and Typescript as a front-end with FastAPI and Pydantic on the backend as “The Mullet Stack”. This article shows you how to use these differing techs together to do web development.
SEAN HELVEY

When str.lower() Is a Security Vulnerability in Python
Some internet standards only support ASCII, which means when Python uses them a translation must happen from the Unicode representation. As the title indicates, this can cause issues. This article shows you why.
SETH LARSON

What’s Missing to Have Reproducible Builds on PyPI
A reproducible build is a way of creating an independently verifiable, repeatable build of CPython and other associated tools. This post explains why Python isn’t there yet and why it is important.
BRETT CANNON

How to Debug Python Code With an AI Agent
Learn AI debugging by pairing with an AI coding agent: reproduce the bug with a failing test, give your agent context, then verify the fix.
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Quiz: How to Debug Python Code With an AI Agent
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How to Use Claude Code to Write and Debug Python
Learn how to use Claude Code to build and debug Python projects with natural-language commands right from your terminal.
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Quiz: How to Use Claude Code to Write and Debug Python
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Nifty Django Feature: Counting on Multiple Columns
The Count expression only works on a single column, but you can use Subquery to count on multiple columns!
TIM SCHILLING


Projects & Code


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PySuricata: Single-Pass Stream-Based Data Profiler
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apkfile: Read, Diff, and Install Android APK Files
GITHUB.COM/DAVID-LEV • Shared by David Lev

emojet: Convert, Find, and Count Emoji in Python
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tortoise-orm: Asyncio ORM Built With Relations in Mind
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matchify: Converts if-else Code to match Statements
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