Fixed #25386 -- Warned about differences between Engine and DjangoTemplates.

Configuring an engine

=====================

If you are simply using the

:class:`~django.template.backends.django.DjangoTemplates` backend, this

probably isn't the documentation you're looking for. An instance of the

``Engine`` class described below is accessible using the ``engine`` attribute

of that backend and any attribute defaults mentioned below are overridden by

what's passed by :class:`~django.template.backends.django.DjangoTemplates`.

.. class:: Engine(dirs=None, app_dirs=False, allowed_include_roots=None, context_processors=None, debug=False, loaders=None, string_if_invalid='', file_charset='utf-8', libraries=None, builtins=None)

    .. versionadded:: 1.8