from django.contrib.auth.models import User
from django.db.models.signals import post_save
from django.db.models.base import ModelBase
from django.db import models

class _UserProfileModelBase(ModelBase):
    # _prepare is not part of the public API and may change
    def _prepare(cls):
        super(_UserProfileModelBase, cls)._prepare()

        def add_profile(sender, instance, created, **kwargs):
            if created:
                cls.objects.create(user=instance)

        # Automatically link profile when a new user is created
        post_save.connect(add_profile, sender=User, weak=False)

class UserProfileModel(models.Model):
    __metaclass__ = _UserProfileModelBase
    user = models.OneToOneField(User, primary_key=True, parent_link=True)

    class Meta:
        abstract = True