Django 1.5: Accessing custom user model fields in models.py

Question

I'm working on a Django 1.5 project and I have a custom user model (let's call it CustomUser). Another app (SomeApp) needs to reference this custom user model. For the purposes of ForeignKey and such, the Django documentation says to use

User = settings.AUTH_USER_MODEL 

However, some functions in SomeApp.models need to access what would have formerly been known as User.objects. But User is now a string and not a class, so User.objects fails. The alternative would be

from django.contrib.auth import get_user_model
User = get_user_model()

Which works in other modules, but when I use this in models.py of SomeApp, Django raises an error:

ImproperlyConfigured("AUTH_USER_MODEL refers to model '%s' that has not been installed" % settings.AUTH_USER_MODEL)

Any ideas?

EDIT 1 - Traceback:

Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "...\django-badger\badger\__init__.py", line 7, in <module>
    from badger.models import Badge, Award, Progress
  File "...\django-badger\badger\models.py", line 26, in <module>
    User = get_user_model()
  File "...\lib\site-packages\django\contrib\auth\__init__.py", line 127, in get_user_model
    raise ImproperlyConfigured("AUTH_USER_MODEL refers to model '%s' that has not been installed" % settings.AUTH_USER_MODEL)
ImproperlyConfigured: AUTH_USER_MODEL refers to model 'MyApp.AuthUser' that has not been installed

EDIT 2 - INSTALLED_APPS settings:

INSTALLED_APPS = (
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.sites',
'django.contrib.messages',
'django.contrib.staticfiles',
'django.contrib.admin',
'django.contrib.admindocs',
'south',
'MyApp',   # this is where my user model is defined
'SomeApp', # I try to use get_user_model() in this app's models.py; doesn't work.
'social_auth',
)

Answer 1

Easy one, I think. I have had so many problems with recursive inclusions and so on... Well, the simplest thing to do, when you add a ForeignKey, is to write it like so:

user = models.ForeignKey(settings.AUTH_USER_MODEL, null=False, on_delete=models.CASCADE, verbose_name=_(u"User"))

If you use get_user_model, do not use it like you do. Calling

User = get_user_model()

at the top of the module will try to import your User model, which may, indeed, not have been "installed". Instead, you have several choices:

• At the top of your module, write

  User = get_user_model # then, you will have to use User() instead of User

• Write get_user_model() everywhere it's useful. Always in methods or functions, never directly in a model module body.