django - Import Class AUTH_USER_MODEL of custom User model into 3 party app -

i need import custom user model third party app, problem app import django's default user model, so:

from django.contrib.auth.models import user 

i have custom user, this:

from myapp.models import user 

but want generic solution.

i had tried:

1:

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

output:

django.core.exceptions.appregistrynotready: models aren't loaded yet. 

2:

from django.conf import settings django.db.models import get_model  app_label, model_name = settings.auth_user_model.split('.') user = get_model(app_label, model_name) 

output:

django.core.exceptions.appregistrynotready: models aren't loaded yet. 

3:

from django.conf import settings user = settings.auth_user_model 

output:

typeerror  isinstance() arg 2 must class, type, or tuple of classes , types 

specifically need execute code

if isinstance(author, user) , author.is_authenticated():     kwargs['author'] = u"%s <%s>" % (author.get_full_name() or author.username, author.email) elif isinstance(author, six.string_types):     kwargs['author'] = author 

how it? thanks

i think "approach 1" right one, problem can't run get_user_model() until after has been loaded. example, change main code to:

if isinstance(author, get_user_model()) , author.is_authenticated():     kwargs['author'] = u"%s <%s>" % (author.get_full_name() or author.username, author.email) elif isinstance(author, six.string_types):     kwargs['author'] = author 

that slow, since runs get_user_model() each time, should find place keep user model run get_user_model() first time code called. example, if code in method of object, put self._user_model = get_user_model() in constructor.

another option check if author string_types first, , then

try:     kwargs['author'] = u"%s <%s>" % (author.get_full_name() or author.username, author.email) except typeerror:     # whatever do, if client code passes wrong kind of object.     pass