Модель
class UserCreationForm(models.Model):

    username = models.CharField(verbose_name='имя пользователя', max_length=28, blank=False,)
    password = models.CharField(verbose_name='пароль', max_length=50, blank=False, )

    def __str__(self):
        return self.title

Представление
class UserCreate(CreateView):
    model = models.UserCreationForm
    fields = ('username', 'password')
    template_name = 'adverts/register.html'

УРЛы
urlpatterns = [
    url(r'^$', views.AdvertList.as_view(), name='home'),
    url(r'^advert/(?P<pk>\d+)/$', views.AdvertDetail.as_view(), name='advert-detail'),
    url(r'^about/$', views.AboutUs.as_view(), name='about-us'),
    url(r'^conditions/$', views.Conditions.as_view(), name='conditions'),
    url(r'author/add/$', views.AdvertCreate.as_view(), name='advert-add'),
    url('^', include('django.contrib.auth.urls')),
    url(r'^admin/', include(admin.site.urls)),
    url(r'^register', views.UserCreate.as_view(), name='register')
]