Sharing Packages between Python 3 installations?
- Python 3 offers a stable ABI option: https://www.python.org/dev/peps/pep-0384/
- It also uses a pyc caching format that allows the same source files to be shared by multiple interpreters without conflict: https://www.python.org/dev/peps/pep-3147/
We should consider whether we want to allow the parallel Python 3 installations to share packages in some manner, such that we don't have to build multiple copies of packages (whether pure Python or with C extensions using the stable ABI) that could actually happily run across all supported Python versions.
For example, if a package supports Python 3.3+, it could be eligible for installation in a shared location that we ensured was added to the default sys.path for all Python 3 versions built for EPEL (after the regular 3.x specific directories).