Make SnapPy an "official" optional package. With the branch apply you just need to run

sage -i snappy

Sadly, the options such as --user are not transmitted to pip. So for a user wide installation, one still need to use pip version

sage -pip install snappy --user

In a follow-up ticket, we could ensure compatibility of the Sage Link class and the SnapPy link class via some doctests.

Note: a Docker image for Sage + SnapPy + Regina + PHCPack + more is available:

• Docker image: https://hub.docker.com/r/computop/sage/
• code repository: https://bitbucket.org/t3m/sagedocker
• dockerfile: https://bitbucket.org/t3m/sagedocker/src/tip/sage/Dockerfile

This ticket is superseded by #31180.

CC: @culler @unhyperbolic @NathanDunfield @miguelmarco @tscrim @slel

Component: packages: optional

Keywords: days74, snappy

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/20739