The Python “Mutable Default Argument” Trap (Why Your List is Not Empty)
This is the most famous “gotcha” in all of Python: the Mutable Default Argument bug. It’s a bug that confuses every developer exactly once. Look…
Packaging Your Python Project: An Intro to pyproject.toml
You’ve built dozens of projects. To publish your package and make it easy for others to install, you’ll need to understand how to use Python…
How to Fix: NotImplementedError in Python (OOP Guide)
This error looks scary, but it’s actually a helpful message from a developer. In Python, the NotImplementedError is not a bug; it’s a feature of…
Understanding pytest Fixtures: A Guide to Better Testing
In our intro to pytest, we learned how to use simple assert statements. But what if all your tests need the same setup data? You…
A Modern Guide to Testing: Why You Should Use pytest
In our unittest guide, we learned how to write automated tests. This Python pytest guide will help you get started with the preferred testing tool….
Python yield Explained: A Deep Dive into Generators
If you’ve ever worked with huge files or infinite sequences, you’ve needed a generator. The keyword that powers them is yield. In this article, you’ll…
Python Dunder Methods: What __init__ and __str__ Really Mean
“Dunder” is short for “Double Underscore.” Dunder methods are special “magic” methods that Python reserves for its own use. You don’t call them directly, but…
Automating Google Sheets with Python (gspread)
We’ve automated Excel, but what about cloud data? If you’re looking to work efficiently with Google Sheets Python integration, gspread is a fantastic library for…
Unpacking with * and **: How to Call Functions with Lists and Dictionaries
You’ve learned how to define a function that accepts *args and **kwargs. Now, we’ll learn the opposite: how to call a function using * and…
How to Fix: RecursionError: maximum recursion depth exceeded
This error means a function is calling itself over and over again, in an infinite loop, until it hits a safety limit set by Python…
