Fixed #20177 - Corrected docs for django.test.utils.setup_test_environment.

    >>> from django.test.utils import setup_test_environment

    >>> setup_test_environment()

:meth:`~django.test.utils.setup_test_environment` installs a template renderer

which will allow us to examine some additional attributes on responses such as

``response.context`` that otherwise wouldn't be available. Note that this

method *does not* setup a test database, so the following will be run against

the existing database and the output may differ slightly depending on what

polls you already created.

Next we need to import the test client class (later in ``tests.py`` we will use

the :class:`django.test.TestCase` class, which comes with its own client, so

this won't be required)::

    >>> from django.test.utils import setup_test_environment

    >>> setup_test_environment()

This convenience method sets up the test database, and puts other

Django features into modes that allow for repeatable testing.

:func:`~django.test.utils.setup_test_environment` puts several Django features

into modes that allow for repeatable testing, but does not create the test

databases; :func:`django.test.simple.DjangoTestSuiteRunner.setup_databases`

takes care of that.

The call to :meth:`~django.test.utils.setup_test_environment` is made

The call to :func:`~django.test.utils.setup_test_environment` is made

automatically as part of the setup of ``./manage.py test``. You only

need to manually invoke this method if you're not using running your

tests via Django's test runner.

.. method:: DjangoTestSuiteRunner.setup_test_environment(**kwargs)

    Sets up the test environment ready for testing.

    Sets up the test environment by calling

    :func:`~django.test.utils.setup_test_environment` and setting

    :setting:`DEBUG` to ``False``.

.. method:: DjangoTestSuiteRunner.build_suite(test_labels, extra_tests=None, **kwargs)