poetry, the python package manager, provides several ways of authenticating against a repository. What isn’t explicitly documented, because it’s an implicit dependency, is that poetry can also use the ~/.netrc file for authentication when fetching packages.
There are several (probably bad) reasons why someone would want to do this vs one of the explicit methods given by poetry. One that comes to mind is needing to install python packages from a private repository from inside a docker container by simply volume mapping the host’s ~/.netrc file to have poetry use the right creds.
This approach probably won’t work when publishing packages — caveat emptor.
While I’m not suggesting that this is a best practice, it’s good to know that it’s an available method in some extreme edge cases.