Is there a built-in login template in Django?

Yes. You can read all about it here: https://docs.djangoproject.com/en/1.8/topics/auth/default/#django.contrib.auth.decorators.login_required … but here are some bullet points:

• add 'django.contrib.auth.middleware.AuthenticationMiddleware' to MIDDLEWARE_CLASSES in settings.py
• add 'django.contrib.auth‘ and 'django.contrib.contenttypes' to INSTALLED_APPS in settings.py
• setup a URL for the login using django.contrib.auth.views.login for the view, such as url(r'^login/$', 'django.contrib.auth.views.login',name="my_login")
• In your view, include the login_required decorator and add it before your view. For example…

views.py…

from django.contrib.auth.decorators import login_required

@login_required
def home(request):
  return HttpResponse('Home Page')

By default, you then put the template inside my_template_directory/registration/login.html . Further info about that template can be found at the link in the beginning of this post.