Python discusses deprecations

The standard, widely-supported solution to that problem (virtualenv/venv) has been part of the standard library since 3.3, and was originally developed outside the stdlib (so you can use it with Python 2 as well). See https://docs.python.org/3/library/venv.html for details.

In short: It magicks up a shell environment in which PYTHONPATH etc. all point to an isolated set of directories which have nothing to do with the system Python. Then you can install whatever you want into that environment, and not have to worry about conflicts with anybody else. It is *not* a full-blown container or VM, or anything nearly as heavy as spinning up a complete instance of Debian.