Would that just create a list of the current packages/versions
Yes, and all downstream dependencies
without actually locking anything?
What do you mean? Nothing stops someone from manually installing an npm package that differs from package-lock.json - this behaves the same. If you pip install -r requirements.txt it installs the exact versions specified by the package maintainer, just like npm install the only difference is python requires you to specify the “lock file” instead of implicitly reading one from the CWD