Cannot create Django user due to UserProfile creation throwing IntegrityError
class UserProfile(models.Model):
    user = models.OneToOneField(User)

    age = models.DateField()
    city = models.CharField(max_length=30)
    state = models.CharField(max_length=20)
    country = models.CharField(max_length=30)
    primary_language = models.CharField(max_length=30)
    secondary_language = models.CharField(max_length=30, blank=True, null=True)
    tertiary_language = models.CharField(max_length=30, blank=True, null=True)

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

post_save.connect(create_user_profile, sender=User)

def create_user_and_profile(request):
    form = RegistrationForm(request.POST)
    if form.is_valid():
        # User is saved to DB here
        user = User.objects.create_user(
            username = form.cleaned_data['username'],
            password = form.cleaned_data['password1'],
            email = form.cleaned_data['email']
        )
        user.first_name = form.cleaned_data['first_name']
        user.last_name = form.cleaned_data['last_name']
        user.save()
        # TODO remaining user creation code goes here
        profile = user.get_profile()

        profile.age = form.cleaned_data['age'],
        profile.city = form.cleaned_data['city'],
        profile.state = form.cleaned_data['state'],
        profile.country = form.cleaned_data['country'],
        profile.primary_language = form.cleaned_data['primary_language'],
        profile.secondary_language = form.cleaned_data['secondary_language'],
        profile.tertiary_language = form.cleaned_data['tertiary_language']
        profile.save()
        return user
    else:
        variables = RequestContext(request, {'form': form})
        return render_to_response('registration/register.html', variables)

profile.first_name = 'abc'
profile.last_name = 'abc'
profile.age = Date(2000, 1, 1)
profile.save()

age = models.DateField()

age = models.DateField(null=True)