Python's STL is such that using it is a code smell. It's better to just use the right tool for the job: you are almost guaranteed to need at least one external library/module for any project of even moderate complexity. So bite the bullet, invest in the time/tooling to do packaging correctly, and use the very excellent Python ecosystem (isn't it why you are using Python to begin with?) that you have at your disposal.

Sticking with the "rusty, leaking batteries included!" in the STL is a bad call and I don't believe it is safe, either; most of the STL is abandonware that is just being shipped for backward compatibility sake. Don't make future product decisions, design decisions etc. based on Python teams' deprecation requirements!

I've been writing Python a long time and have grown quite frustrated by some of its warts. But every time I look at seriously investing in another language attrs is one of the few things I wouldn't want to give up. It's not perfect but I'll take very, very good when I can get it, yeah?