Python Pitfalls: Common Mistakes and How to Avoid Them

What are common mistakes that Python beginners make, and how do you avoid them? Christopher Trudeau is back on the show this week with another batch of PyCoder’s Weekly articles and projects.

We dig into an article about common pitfalls and mistakes new Python developers make. Some of the mistakes are due to Python doing exactly what you asked it to do. We also talk about Real Python resources for getting started with the language and building your development environment.

We also share other articles and projects from the Python community, including recent releases, a collection of new PEPs, and the results of two recent Python elections. We cover creating temporary files in Python, decoupling pure logic from Django’s ORM, a Python functions reference, a lightning-fast logger, and an online development environment for creating games.

Course Spotlight: How to Use Python: Taking Your First Steps

Take your first steps with Python. Install it, run your first program, and work with variables, data types, loops, functions, and errors.

Live Course Spotlight: Python for Beginners: Code With Confidence

Learn the fundamentals of Python step-by-step in a friendly, interactive cohort. Build confidence writing code and understand the “why” behind Python’s core concepts.

Free Kit: Get the Python Beginner Starter Kit with a cheat sheet, a sample book chapter, a course, and a quiz. You only need a free Real Python account.

Topics:

• 00:00:00 – Introduction
• 00:02:05 – After a delay - Python 3.15.0 (final) is here!
• 00:02:41 – Python 3.10.22, 3.11.17, 3.12.15, 3.13.16 and 3.14.8 are now available!
• 00:03:30 – PEP 823 – None-aware access operators
• 00:04:40 – PEP 845: Leading-Dot Value Patterns
• 00:05:04 – PEP 846: Docstrings for Type Aliases
• 00:05:21 – PEP 848: Generational Incremental Garbage Collection
• 00:06:12 – 2026 PSF Board Election Results
• 00:06:31 – 2026 Python Packaging Council Election Results!
• 00:07:23 – 7 Python Mistakes Beginners Make
• 00:18:03 – An Effective Python Development Environment
• 00:21:37 – Creating Temporary Files in Python
• 00:24:30 – Video Course Spotlight
• 00:26:02 – 5 Design Patterns Used in My New Habit Tracker App
• 00:33:43 – Functions: A Complete Reference
• 00:36:50 – PYXEL STUDIO
• 00:39:38 – pyfastlogging: A Lightning Fast Logger, Written in Rust
• 00:41:54 – How Libraries Run Rust Inside Python (with PyO3)
• 00:44:43 – Thanks and goodbye

News:

• Python 3.15.0 (final) is here!
• Python 3.10.22, 3.11.17, 3.12.15, 3.13.16 and 3.14.8 are now available!
• PEP 823 – None-aware access operators
• PEP 824 – None-coalescing operators
• PEP 845: Leading-Dot Value Patterns (Draft)
• PEP 846: Docstrings for Type Aliases (Draft)
• PEP 848: Generational Incremental Garbage Collection (Draft)
• 2026 PSF Board Election Results
• 2026 Python Packaging Council Election Results!

Show Links:

• 7 Python Mistakes Beginners Make – Some mistakes are because Python did exactly what you asked it to do. This article covers seven of them. For each one, you get the hidden cause, plus the first thing worth checking.
• An Effective Python Development Environment – Choose a Python development environment that helps you get coding. Find tutorials and courses on editors, uv, virtual environments, and useful tools.
• Creating Temporary Files in Python – How to create temporary files and directories in Python using the tempfile module’s NamedTemporaryFile and TemporaryDirectory.
• 5 Design Patterns Used in My New Habit Tracker App – Bob has built a Django + HTMX-based habit tracker. This article covers five small Python and design patterns used in his code.
• Functions: A Complete Reference – This article is a complete reference for all things related to functions in Python, including structure, signatures, *args, **kwargs, using functions as objects, and more.

Projects:

• PYXEL STUDIO
• pyfastlogging: A Lightning Fast Logger, Written in Rust

Additional Links:

• Install packages in a virtual environment using pip and venv - Python Packaging User Guide
• Python Virtual Environments: A Primer – Real Python
• Require a Virtualenv for pip Installs - pydevtools
• One namespace to namespace them all (Python Language Summit 2026) - Python Insider
• commitgraph - Commit to what matters. Every day.
• Getting Started with Rust as Python Devs - Talk Python To Me Podcast
• How Libraries Run Rust Inside Python (with PyO3) - Bob Belderbos

Level up your Python skills with our expert-led courses:

• Python Basics: Setting Up Python
• Python Basics: Code Your First Python Program
• How to Use Python: Taking Your First Steps

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