Import error at setting COMMENTS_XTD_MODEL

[scorpion-HF]

I have an app named commenting and a model named BookComment
so I set COMMENTS_XTD_MODEL='commenting.models.BookComment'
and got this error:
ImportError: Module "commenting.models" does not define a "BookComment" attribute/class
and hear my commenting.models.py:
from django_comments_xtd.models import XtdComment
from django.db import models

class BookComment(XtdComment):
pass
what can I do?
can it be a classic circular dependency problem?

[danirus]

Does the commenting directory have an __init__.py?
Did you add commenting to your INSTALLED_APPS?
Does it have an app.py module? With what content?
Check that, and maybe you could share your app directory. Also the examples directory contains a demo that extends django_comments_xtd in the same way you want to do it, here.

[scorpion-HF]

yes commenting directory has init.py
I did add commenting to my INSTALLED_APPS
It also has app.py like this:

from django.apps import AppConfig

class CommentingConfig(AppConfig):
name = 'commenting'
and here is my project directory :
book_store
|
book_store
catalog
commenting
|
migrations
templates
init.py
apps.py
models.py
views.py
admin.py
tests.py
urls.py
users
media
this is my project repository you can check it:
https://github.com/scorpion-HF/book_store.git
I wandted to override get_absolute_url of comment model so I was not successful so I overrode a view of the original app
you can see it at my project

[danirus]

If you see the call stack when it fails you can see that the problem is produced by the imports in the models.py module. If you comment the imports that you don't need in commenting.models you fix the problem.

Good luck with the project! ;-)