[Python] How does Python decide whether the last part of an imported name is a module or a...

My first question is whether the code in main.py is valid?

This is main.py:

import foo.bar as fb
fb()


This is foo/__init__.py:

from .bar import * # DELETE THIS
bar = lambda: print('lambda bar')


foo/bar.py is empty. Python version is 3.12.3.

The second question is why deleting the first line from foo/__init__.py causes an error "TypeError: 'module' object is not callable"? Is this undefined behavior, implementation defined or documented somewhere? How does Python decide whether an imported name refers to a function or a submodule?

Continue reading...