[1.3.X] Fixed #16552: Noted that contrib.sessions is a requirement for the...

    1. Add ``'django.contrib.admin'`` to your :setting:`INSTALLED_APPS`

       setting.

    2. Admin has two dependencies - :mod:`django.contrib.auth` and

       :mod:`django.contrib.contenttypes`. If these applications are not

    2. The admin has four dependencies - :mod:`django.contrib.auth`,

       :mod:`django.contrib.contenttypes`,

       :mod:`django.contrib.messages` and

       :mod:`django.contrib.sessions`.  If these applications are not

       in your :setting:`INSTALLED_APPS` list, add them.

    3. Determine which of your application's models should be editable in the