[FIXED] Python relative import reexport

Issue

I am writing a python package that I intend to use for some projects I am working on. I do not want this package to be in a public package index, so I am currently using git submodules to easily set it up in projects. Every import inside the package is relative.

My package's structure looks like this:

package
|---__init__.py
|---src
    |---__init__.py
    |---core
        |---__init__.py
        |---types.py
        |---interfaces.py
|---test

I want to make some modules more accessible, so the top level __init__.py file of my package has some lines like this:

from .src.core import types
from .src.core import interfaces

The problem

I place the python package somewhere in my project:

project
|---__init__.py
|---main.py
|---package

in the main file, i can do the following:

from package import types

def foo(param: types.Foo):
    ...

but I want to do:

from package.types import Foo # raises ModuleNotFoundError: No module named 'package.types'

I can't find the reason why this happens nor how to solve it. I don't want to publish the package to a public package index and I doubt I can get access to a private one.

Solution

I've gone through python's import system documentation and found out the root of the issue. Altough package.types is a module, it is not a direct reference to a module, but rather to the types object from package. This means that it can only be accessed after package is explicitly imported.

Knowing this, the solution is quite simple: create a types.py python file inside package that contains the reexports.

First, add a types.py file in the top level directory of the package:

package
|---__init__.py
|---types.py <-- add this
|---src
    |---__init__.py
    |---core
        |---__init__.py
        |---types.py
        |---interfaces.py
|---test

Then, the types.py file imports the types I want to reexport:

from src.core.types import Foo

Now the types can be accessed both ways:

from package import types

def foo(param: types.Foo):
    ...

from package.types import Foo

def foo(param: Foo):
    ...

Answered By - Pollastre