django authentication package: 'auth' not registered as a namespace

for Django 2.0 syntax should be like this

    from django.urls import path
    path('accounts/', include('django.contrib.auth.urls')),

    <li><a href="{% url 'auth:login' %}">Login</a></li>#do not use this in any template
    <li><a href="{% url 'login' %}">Login</a></li>#use this in your template