Lab: what a library costs to install and to import¶

For each of eight libraries: a fresh virtual environment, an install of the bare package, the number of distributions that came with it, the megabytes on disk, and the best of five import times for the package root — then the same with one extra, so the difference is the extra's price. Finally, what reaching for a feature an extra provides says when the extra is not installed.

uv venv --python 3.13 .venv
.venv/bin/python footprint.py       # it creates its own throwaway venv per package