Pytest-console-scripts is a pytest plugin for running python scripts from within
tests. It's quite similar to subprocess.run(), but it also has an in-process
mode, where the scripts are executed by the interpreter that's running pytest
(using some amount of sandboxing).

In-process mode significantly reduces the run time of the test suites that run
many external scripts. This is speeds up development. In the CI environment
subprocess mode can be used to make sure the scripts also work (and behave the
same) when run by a fresh interpreter.