How to Mock Environment Variables in Python’s unittest

Sometimes tests need to change environment variables. This is fairly straightforward in tests using Python’s unittest, thanks to os.environ quacking like a dict, and the unittest.mock.patch.dict decorator/context manager.

How to Mock Environment Variables in pytest

Sometimes tests need to change environment variables. This is fairly straightforward in pytest, thanks to os.environ quacking like a dict, and the unittest.mock.patch.dict decorator/context manager.

How to Unit Test a Django Management Command

This post is an adapted extract from my book Speed Up Your Django Tests, available now.

A Guide to Python Lambda Functions

This is a cross-post from the Scout APM blog, where I occasionally write. I also maintain the Scout Python integration.

Better Python Decorators with wrapt

This is a cross-post from the Scout APM blog, where I occasionally write. I also maintain the Scout Python integration, which uses wrapt for its Python decorators.

Why does Python raise ModuleNotFoundError when modifying Django's INSTALLED_APPS?

Imagine we are installing the third party package django-cors-headers, which I maintain. Step one in its installation process is to install the package, so we run the command: