Issue #684

NumPy Type Hints, LEGB, Pyrefly vs ty, and More

June 3, 2025

NumPy Type Hints, LEGB, Pyrefly vs ty, and More
#684 – JUNE 3, 2025 VIEW IN BROWSER
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NumPy Array Type Hints
Thanks to improvements in NumPy typing support, NumPy generic arrays can now type both shape and dtype, offering opportunities for improved static analysis and run-time validation.
CHRISTOPHER ARIZA • Shared by Christopher Ariza

The LEGB Rule & Understanding Python Scope
In this step-by-step video course, you’ll learn what scopes are, how they work, and how to use them effectively to avoid name collisions in your code.
REAL PYTHON course

Prevent Postgres Slowdowns on Python Apps with this Check List
Avoid performance regressions in your Python app by staying on top of Postgres maintenance. This monthly check list outlines what to monitor, how to catch slow queries early, and ways to ensure indexes, autovacuum, and I/O are performing as expected →
PGANALYZEsponsor

Pyrefly vs. ty: Comparing Python’s New Type Checkers
A deep dive on Python’s two newest, Rust-based type checkers. This post includes both performance and capability comparisons.
EDWARD LI

Python Release 3.14.0b2
PYTHON.ORG

PyBay 2025 Call for Proposals Due June 8
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Discussions


Django Forum: Supporting t-strings
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Ruff Users: What Rules Are Using and What Are You Ignoring?
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Python Jobs


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Articles & Tutorials


Journey Into Real Python
Amanda has recently written her first article for Real Python and this post talks about her experience doing so. If you want to check out the article, it is on Nested Loops.
AMANDA ENE ADOYI

Ways to Optimize Your Code in Python
Learn four ways to optimize your Python project and improve performance, including choosing the right data structures, variable scopes, list comprehensions and generators, and how to leverage built-in libraries.
FEDERICO TROTTA • Shared by AppSignal

DumPy: NumPy Except It’s OK if You’re Dum
In a follow-up to the article I Don’t Like NumPy, this post proposes a way of writing code that looks like loops but use vector operations instead.
DYNOMIGHT.NET

How to Split Up a Django Monolith Without Microservices
Facing too much complexity in your Django application as a developer? This articles introduces django-queuebie, a synchronous message queue working with commands and events.
RONNY VEDRILLA • Shared by Ronny Vedrilla

Control Flow Structures in Python
Take control of your code with Python control flow structures. You’ll learn with real examples using loops, conditionals, try-except blocks, and pattern matching.
REAL PYTHON

Quiz: Control Flow Structures in Python
REAL PYTHON

Python pandas Ditches NumPy for Speedier PyArrow
Pandas 3.0 will significantly boost performance by replacing NumPy with PyArrow as its default engine, enabling faster loading and reading of columnar data.
JOAB JACKSON

Writing Portable DataFrame Code for Lazy Execution
Learn one simple concept, and you can rid your code of row-ordering assumptions - it will then work seamlessly across eager and lazy DataFrames
MARCO GORELLI • Shared by Marco Gorelli

Marimo: A Reactive, Reproducible Notebook
Discover how marimo notebook simplifies coding with reactive updates, UI elements, and sandboxing for safe, sharable notebooks.
REAL PYTHON

Quiz: Marimo: A Reactive, Reproducible Notebook
REAL PYTHON

Another Great PyCon
A post about the highlights of PyCon US 2025 from one of the volunteers.
GEORGI KER

Pointblank: Data Validation for DataFrames and DBs
POSIT-DEV.GITHUB.IO • Shared by Richard Iannone


Projects & Code


Brought to you by Real Python for Teamssponsor
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skylos: Detect Dead Code
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samps: Serial Port I/O Access
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whatsonpypi: Check PyPI From the Command Line
GITHUB.COM/VISESHRP • Shared by visesh prasad

mutmut: Mutation Testing System
GITHUB.COM/BOXED

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