DjangoでURLルーティングの階層化

urls.py

urlpatterns = [
    url(r"^mysite/", include([
        url(r"^accounts/", include([
            url(r"^login/$", auth_views.login, {"template_name": "accounts/login.html"}, name="login"),
            url(r"^logout/$", auth_views.logout, name="logout"),
        ], namespace="accounts", app_name="accounts")),

        url(r'^admin/', admin.site.urls),
        url(r'^', include('app.urls')),
    ]))
]