making __main__ a __package__

to make an interactive computing session, or a python module generally, appear like a package we need to set two varaiables.

    import pytest; from pathlib import Path

there is a python file one directory up called mkdocs.py. we should be able to get at this file, and we will.

our first transgression is not being a package.

    with pytest.raises(ImportError, match="attempted relative import with no known parent package"):
        from . import mkdocs

to be a package we need __package__ and __path__

    __package__, __path__ = __name__, [""]

the __path__ contains the lookup directories for parts of the package; this is a feature of namespace packages AND where shit gets weird.

now that we quack like a package we can attempt relative imports, but mkdocs.py is still out of reach.

    with pytest.raises(ImportError, match="cannot import name 'mkdocs' from '__main__' \(unknown location\)"):
        from . import mkdocs

append the parent to the __path__

    __path__ += [".."]

and boom!

    from . import mkdocs#!

how is this different from sys.paths

it is probably not much different, but more a cheat code you can abuse at your own ⚠