Check if a package will install in another version of Python

Also known as (potentially) solving the "Could not build wheels for [package]" error message.

The problem

Sometimes when you try to install a package you get an error. What's the error? Could be anything!

A big one is "could not build wheels for [package]," which means two things:

1. pip couldn't find a version of the package pre-built for your system (combination of your Python version + your operating system)
2. It tried to take the source code and turn it into a package, but something went wrong.

Figuring out the second half is probably the "correct" way to fix things long term, but changing your Python version is often a quicker fix if there happens to be a pre-built version for another.

Update uv

Did you install Python using uv?. I hope so, because we're going to take advantage of that!

We'll start by updating uv so it knows about recent Python releases.

macOS Windows

brew upgrade uv

scoop update uv

Determining which other Python version to try

First, check the version of Python you're running:

python --version

Then, find the versions of Python that uv knows about:

uv python list

Scroll all the way up to the top to see something that looks a little bit earlier than yours.

For example, if I'm using Python 3.13 I might want to dial back to Python 3.12.

Installing and testing

Since we are interested in scaling back to Python 3.12, we'll start by installing Python 3.12 with uv.

uv python install 3.12

Then we'll make a temporary environment that uses Python 3.12.

macOS Windows

uv venv ~/.venvs/test-3.12 --python 3.12
source ~/.venvs/test-3.12/bin/activate

uv venv %USERPROFILE%\.venvs\test-3.12 --python 3.12
%USERPROFILE%\.venvs\test-3.12\Scripts\activate

Then we'll try to install the dedupe package in that Python 3.12 environment.

python -m pip install dedupe

Did it work? If so, you can use that environment for the project that needs an older Python.

Cleanup

If you change the environment you're using, you'll probably end up having to reinstall a lot of packages for your new Python version, along with setting up Jupyter to point to the right place.

# Reinstall some libraries
python -m pip install requests bs4 pandas

# Change Jupyter to use the current command-line Python
python -m pip install ipykernel
python -m ipykernel install --user