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django/docs/internals/deprecation.txt

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===========================
Django Deprecation Timeline
===========================
This document outlines when various pieces of Django will be removed or altered
in a backward incompatible way, following their deprecation, as per the
:ref:`deprecation policy <internal-release-deprecation-policy>`. More details
about each item can often be found in the release notes of two versions prior.
.. _deprecation-removed-in-2.0:
2.0
---
See the :ref:`Django 1.8 release notes<deprecated-features-1.8>` for more
details on these changes.
* Support for calling a ``SQLCompiler`` directly as an alias for calling its
``quote_name_unless_alias`` method will be removed.
* ``cycle`` and ``firstof`` template tags will be removed from the ``future``
template tag library (used during the 1.6/1.7 deprecation period).
* ``django.conf.urls.patterns()`` will be removed.
* Support for the ``prefix`` argument to
``django.conf.urls.i18n.i18n_patterns()`` will be removed.
* ``SimpleTestCase.urls`` will be removed.
* Using an incorrect count of unpacked values in the ``for`` template tag
will raise an exception rather than fail silently.
* The ``DatabaseCreation`` class on each database backend will be removed,
and all table/schema editing will be moved to be via ``SchemaEditor`` instead.
* The ability to :func:`~django.core.urlresolvers.reverse` URLs using a dotted
Python path will be removed.
* Support for :py:mod:`optparse` will be dropped for custom management commands
(replaced by :py:mod:`argparse`).
* The class :class:`~django.core.management.NoArgsCommand` will be removed. Use
:class:`~django.core.management.BaseCommand` instead, which takes no arguments
by default.
* ``django.db.models.sql.aggregates`` module will be removed.
* ``django.contrib.gis.db.models.sql.aggregates`` module will be removed.
* The following methods and properties of ``django.db.sql.query.Query`` will
be removed:
* Properties: ``aggregates`` and ``aggregate_select``
* Methods: ``add_aggregate``, ``set_aggregate_mask``, and
``append_aggregate_mask``.
* ``django.template.resolve_variable`` will be removed.
* The ``error_message`` argument of ``django.forms.RegexField`` will be removed.
* The ``unordered_list`` filter will no longer support old style lists.
* Support for string ``view`` arguments to ``url()`` will be removed.
* The backward compatible shim to rename ``django.forms.Form._has_changed()``
to ``has_changed()`` will be removed.
* The ``removetags`` template filter will be removed.
* The ``remove_tags()`` and ``strip_entities()`` functions in
``django.utils.html`` will be removed.
* The ``is_admin_site`` argument to
``django.contrib.auth.views.password_reset()`` will be removed.
* ``django.db.models.field.subclassing.SubfieldBase`` will be removed.
* ``django.utils.checksums`` will be removed; its functionality is included
in django-localflavor 1.1+.
* The ``original_content_type_id`` attribute on
``django.contrib.admin.helpers.InlineAdminForm`` will be removed.
* The backwards compatibility shim to allow ``FormMixin.get_form()`` to be
defined with no default value for its ``form_class`` argument will be removed.
* The backwards compatibility alias ``django.template.loader.BaseLoader`` will
be removed.
* The ``dirs`` parameter for the following functions will be removed:
* ``django.template.loader.get_template()``
* ``django.template.loader.select_template()``
* ``django.shortcuts.render()``
* ``django.shortcuts.render_to_response()``
.. _deprecation-removed-in-1.9:
1.9
---
See the :ref:`Django 1.7 release notes<deprecated-features-1.7>` for more
details on these changes.
* ``django.utils.dictconfig`` will be removed.
* ``django.utils.importlib`` will be removed.
* ``django.utils.tzinfo`` will be removed.
* ``django.utils.unittest`` will be removed.
* The ``syncdb`` command will be removed.
* ``django.db.models.signals.pre_syncdb`` and
``django.db.models.signals.post_syncdb`` will be removed.
* ``allow_syncdb`` on database routers will no longer automatically become
``allow_migrate``.
* The legacy method of syncing apps without migrations will be removed,
and migrations will become compulsory for all apps. This includes automatic
loading of ``initial_data`` fixtures and support for initial SQL data.
* All models will need to be defined inside an installed application or
declare an explicit :attr:`~django.db.models.Options.app_label`.
Furthermore, it won't be possible to import them before their application
is loaded. In particular, it won't be possible to import models inside
the root package of their application.
* If models are organized in a package, Django will no longer look for
:ref:`initial SQL data<initial-sql>` in ``myapp/models/sql/``. Move your
custom SQL files to ``myapp/sql/``.
* The model and form ``IPAddressField`` will be removed.
* ``AppCommand.handle_app()`` will no longer be supported.
* ``RequestSite`` will be located in ``django.contrib.sites.requests`` and
``get_current_site`` in ``django.contrib.sites.shortcuts``.
* FastCGI support via the ``runfcgi`` management command will be
removed. Please deploy your project using WSGI.
* ``django.utils.datastructures.SortedDict`` will be removed. Use
:class:`collections.OrderedDict` from the Python standard library instead.
* ``ModelAdmin.declared_fieldsets`` will be removed.
* Instances of ``util.py`` in the Django codebase have been renamed to
``utils.py`` in an effort to unify all util and utils references.
The modules that provided backwards compatibility will be removed:
* ``django.contrib.admin.util``
* ``django.contrib.gis.db.backends.util``
* ``django.db.backends.util``
* ``django.forms.util``
* ``ModelAdmin.get_formsets`` will be removed.
* Remove the backward compatible shims introduced to rename the
``BaseMemcachedCache._get_memcache_timeout()`` method to
``get_backend_timeout()``.
* The ``--natural`` and ``-n`` options for :djadmin:`dumpdata` will be removed.
Use :djadminopt:`--natural-foreign` instead.
* The ``use_natural_keys`` argument for ``serializers.serialize()`` will be
removed. Use ``use_natural_foreign_keys`` instead.
* ``django.forms.get_declared_fields`` will be removed.
* The ability to use a ``SplitDateTimeWidget`` with ``DateTimeField`` will be
removed.
* The ``WSGIRequest.REQUEST`` property will be removed.
* The class ``django.utils.datastructures.MergeDict`` will be removed.
* The ``zh-cn`` and ``zh-tw`` language codes will be removed and have been
replaced by the ``zh-hans`` and ``zh-hant`` language code respectively.
* The internal ``django.utils.functional.memoize`` will be removed.
* ``django.core.cache.get_cache`` will be removed. Add suitable entries
to :setting:`CACHES` and use :data:`django.core.cache.caches` instead.
* ``django.db.models.loading`` will be removed.
* Passing callable arguments to querysets will no longer be possible.
* ``BaseCommand.requires_model_validation`` will be removed in favor of
``requires_system_checks``. Admin validators will be replaced by admin
checks.
* ``ModelAdmin.validator`` will be removed in favor of the new ``checks``
attribute.
* ``django.db.backends.DatabaseValidation.validate_field`` will be removed in
favor of the ``check_field`` method.
* ``django.utils.module_loading.import_by_path`` will be removed in favor of
``django.utils.module_loading.import_string``.
* ``ssi`` and ``url`` template tags will be removed from the ``future`` template
tag library (used during the 1.3/1.4 deprecation period).
* ``django.utils.text.javascript_quote`` will be removed.
* Database test settings as independent entries in the database settings,
prefixed by ``TEST_``, will no longer be supported.
* The `cache_choices` option to :class:`~django.forms.ModelChoiceField` and
:class:`~django.forms.ModelMultipleChoiceField` will be removed.
* The default value of the
:attr:`RedirectView.permanent <django.views.generic.base.RedirectView.permanent>`
attribute will change from ``True`` to ``False``.
.. _deprecation-removed-in-1.8:
1.8
---
See the :ref:`Django 1.6 release notes<deprecated-features-1.6>` for more
details on these changes.
* ``django.contrib.comments`` will be removed.
* The following transaction management APIs will be removed:
- ``TransactionMiddleware``,
- the decorators and context managers ``autocommit``, ``commit_on_success``,
and ``commit_manually``, defined in ``django.db.transaction``,
- the functions ``commit_unless_managed`` and ``rollback_unless_managed``,
also defined in ``django.db.transaction``,
- the ``TRANSACTIONS_MANAGED`` setting.
Upgrade paths are described in the :ref:`transaction management docs
<transactions-upgrading-from-1.5>`.
* The :ttag:`cycle` and :ttag:`firstof` template tags will auto-escape their
arguments. In 1.6 and 1.7, this behavior is provided by the version of these
tags in the ``future`` template tag library.
* The ``SEND_BROKEN_LINK_EMAILS`` setting will be removed. Add the
:class:`django.middleware.common.BrokenLinkEmailsMiddleware` middleware to
your :setting:`MIDDLEWARE_CLASSES` setting instead.
* ``django.middleware.doc.XViewMiddleware`` will be removed. Use
``django.contrib.admindocs.middleware.XViewMiddleware`` instead.
* ``Model._meta.module_name`` was renamed to ``model_name``.
* Remove the backward compatible shims introduced to rename ``get_query_set``
and similar queryset methods. This affects the following classes:
``BaseModelAdmin``, ``ChangeList``, ``BaseCommentNode``,
``GenericForeignKey``, ``Manager``, ``SingleRelatedObjectDescriptor`` and
``ReverseSingleRelatedObjectDescriptor``.
* Remove the backward compatible shims introduced to rename the attributes
``ChangeList.root_query_set`` and ``ChangeList.query_set``.
* ``django.views.defaults.shortcut`` will be removed, as part of the
goal of removing all ``django.contrib`` references from the core
Django codebase. Instead use
``django.contrib.contenttypes.views.shortcut``. ``django.conf.urls.shortcut``
will also be removed.
* Support for the Python Imaging Library (PIL) module will be removed, as it
no longer appears to be actively maintained & does not work on Python 3.
You are advised to install `Pillow`_, which should be used instead.
.. _`Pillow`: https://pypi.python.org/pypi/Pillow
* The following private APIs will be removed:
- ``django.db.backend``
- ``django.db.close_connection()``
- ``django.db.backends.creation.BaseDatabaseCreation.set_autocommit()``
- ``django.db.transaction.is_managed()``
- ``django.db.transaction.managed()``
* ``django.forms.widgets.RadioInput`` will be removed in favor of
``django.forms.widgets.RadioChoiceInput``.
* The module ``django.test.simple`` and the class
``django.test.simple.DjangoTestSuiteRunner`` will be removed. Instead use
``django.test.runner.DiscoverRunner``.
* The module ``django.test._doctest`` will be removed. Instead use the doctest
module from the Python standard library.
* The ``CACHE_MIDDLEWARE_ANONYMOUS_ONLY`` setting will be removed.
* Usage of the hard-coded *Hold down "Control", or "Command" on a Mac, to select
more than one.* string to override or append to user-provided ``help_text`` in
forms for ManyToMany model fields will not be performed by Django anymore
either at the model or forms layer.
* The ``Model._meta.get_(add|change|delete)_permission`` methods will
be removed.
* The session key ``django_language`` will no longer be read for backwards
compatibility.
* Geographic Sitemaps will be removed
(``django.contrib.gis.sitemaps.views.index`` and
``django.contrib.gis.sitemaps.views.sitemap``).
* ``django.utils.html.fix_ampersands``, the ``fix_ampersands`` template filter and
``django.utils.html.clean_html`` will be removed following an accelerated deprecation.
.. _deprecation-removed-in-1.7:
1.7
---
See the :ref:`Django 1.5 release notes<deprecated-features-1.5>` for more
details on these changes.
* The module ``django.utils.simplejson`` will be removed. The standard library
provides :mod:`json` which should be used instead.
* The function ``django.utils.itercompat.product`` will be removed. The Python
builtin version should be used instead.
* Auto-correction of INSTALLED_APPS and TEMPLATE_DIRS settings when they are
specified as a plain string instead of a tuple will be removed and raise an
exception.
* The ``mimetype`` argument to the ``__init__`` methods of
:class:`~django.http.HttpResponse`,
:class:`~django.template.response.SimpleTemplateResponse`, and
:class:`~django.template.response.TemplateResponse`, will be removed.
``content_type`` should be used instead. This also applies to the
:func:`~django.shortcuts.render_to_response` shortcut and
the sitemap views, :func:`~django.contrib.sitemaps.views.index` and
:func:`~django.contrib.sitemaps.views.sitemap`.
* When :class:`~django.http.HttpResponse` is instantiated with an iterator,
or when :attr:`~django.http.HttpResponse.content` is set to an iterator,
that iterator will be immediately consumed.
* The ``AUTH_PROFILE_MODULE`` setting, and the ``get_profile()`` method on
the User model, will be removed.
* The ``cleanup`` management command will be removed. It's replaced by
``clearsessions``.
* The ``daily_cleanup.py`` script will be removed.
* The ``depth`` keyword argument will be removed from
:meth:`~django.db.models.query.QuerySet.select_related`.
* The undocumented ``get_warnings_state()``/``restore_warnings_state()``
functions from :mod:`django.test.utils` and the ``save_warnings_state()``/
``restore_warnings_state()``
:ref:`django.test.*TestCase <django-testcase-subclasses>` methods are
deprecated. Use the :class:`warnings.catch_warnings` context manager
available starting with Python 2.6 instead.
* The undocumented ``check_for_test_cookie`` method in
:class:`~django.contrib.auth.forms.AuthenticationForm` will be removed
following an accelerated deprecation. Users subclassing this form should
remove calls to this method, and instead ensure that their auth related views
are CSRF protected, which ensures that cookies are enabled.
* The version of :func:`django.contrib.auth.views.password_reset_confirm` that
supports base36 encoded user IDs
(``django.contrib.auth.views.password_reset_confirm_uidb36``) will be
removed. If your site has been running Django 1.6 for more than
:setting:`PASSWORD_RESET_TIMEOUT_DAYS`, this change will have no effect. If
not, then any password reset links generated before you upgrade to Django 1.7
won't work after the upgrade.
* The ``django.utils.encoding.StrAndUnicode`` mix-in will be removed.
Define a ``__str__`` method and apply the
:func:`~django.utils.encoding.python_2_unicode_compatible` decorator instead.
.. _deprecation-removed-in-1.6:
1.6
---
See the :ref:`Django 1.4 release notes<deprecated-features-1.4>` for more
details on these changes.
* ``django.contrib.databrowse`` will be removed.
* ``django.contrib.localflavor`` will be removed following an accelerated
deprecation.
* ``django.contrib.markup`` will be removed following an accelerated
deprecation.
* The compatibility modules ``django.utils.copycompat`` and
``django.utils.hashcompat`` as well as the functions
``django.utils.itercompat.all`` and ``django.utils.itercompat.any`` will
be removed. The Python builtin versions should be used instead.
* The ``csrf_response_exempt`` and ``csrf_view_exempt`` decorators will
be removed. Since 1.4 ``csrf_response_exempt`` has been a no-op (it
returns the same function), and ``csrf_view_exempt`` has been a
synonym for ``django.views.decorators.csrf.csrf_exempt``, which should
be used to replace it.
* The ``django.core.cache.backends.memcached.CacheClass`` backend
was split into two in Django 1.3 in order to introduce support for
PyLibMC. The historical ``CacheClass`` will be removed in favor of
``django.core.cache.backends.memcached.MemcachedCache``.
* The UK-prefixed objects of ``django.contrib.localflavor.uk`` will only
be accessible through their GB-prefixed names (GB is the correct
ISO 3166 code for United Kingdom).
* The ``IGNORABLE_404_STARTS`` and ``IGNORABLE_404_ENDS`` settings have been
superseded by :setting:`IGNORABLE_404_URLS` in the 1.4 release. They will be
removed.
* The form wizard has been refactored to use class-based views with pluggable
backends in 1.4. The previous implementation will be removed.
* Legacy ways of calling
:func:`~django.views.decorators.cache.cache_page` will be removed.
* The backward-compatibility shim to automatically add a debug-false
filter to the ``'mail_admins'`` logging handler will be removed. The
:setting:`LOGGING` setting should include this filter explicitly if
it is desired.
* The builtin truncation functions ``django.utils.text.truncate_words()``
and ``django.utils.text.truncate_html_words()`` will be removed in
favor of the ``django.utils.text.Truncator`` class.
* The :class:`~django.contrib.gis.geoip.GeoIP` class was moved to
:mod:`django.contrib.gis.geoip` in 1.4 -- the shortcut in
:mod:`django.contrib.gis.utils` will be removed.
* ``django.conf.urls.defaults`` will be removed. The functions
:func:`~django.conf.urls.include`, :func:`~django.conf.urls.patterns` and
:func:`~django.conf.urls.url` plus :data:`~django.conf.urls.handler404`,
:data:`~django.conf.urls.handler500`, are now available through
:mod:`django.conf.urls` .
* The functions ``setup_environ()`` and ``execute_manager()`` will be removed
from :mod:`django.core.management`. This also means that the old (pre-1.4)
style of :file:`manage.py` file will no longer work.
* Setting the ``is_safe`` and ``needs_autoescape`` flags as attributes of
template filter functions will no longer be supported.
* The attribute ``HttpRequest.raw_post_data`` was renamed to ``HttpRequest.body``
in 1.4. The backward compatibility will be removed --
``HttpRequest.raw_post_data`` will no longer work.
* The value for the ``post_url_continue`` parameter in
``ModelAdmin.response_add()`` will have to be either ``None`` (to redirect
to the newly created object's edit page) or a pre-formatted url. String
formats, such as the previous default ``'../%s/'``, will not be accepted any
more.
.. _deprecation-removed-in-1.5:
1.5
---
See the :ref:`Django 1.3 release notes<deprecated-features-1.3>` for more
details on these changes.
* Starting Django without a :setting:`SECRET_KEY` will result in an exception
rather than a ``DeprecationWarning``. (This is accelerated from the usual
deprecation path; see the :doc:`Django 1.4 release notes</releases/1.4>`.)
* The ``mod_python`` request handler will be removed. The ``mod_wsgi``
handler should be used instead.
* The ``template`` attribute on ``django.test.client.Response``
objects returned by the :ref:`test client <test-client>` will be removed.
The :attr:`~django.test.Response.templates` attribute should be
used instead.
* The ``django.test.simple.DjangoTestRunner`` will be removed.
Instead use a unittest-native class. The features of the
``django.test.simple.DjangoTestRunner`` (including fail-fast and
Ctrl-C test termination) can currently be provided by the unittest-native
:class:`~unittest.TextTestRunner`.
* The undocumented function
``django.contrib.formtools.utils.security_hash`` will be removed,
instead use ``django.contrib.formtools.utils.form_hmac``
* The function-based generic view modules will be removed in favor of their
class-based equivalents, outlined :doc:`here
</topics/class-based-views/index>`.
* The ``django.core.servers.basehttp.AdminMediaHandler`` will be
removed. In its place use
``django.contrib.staticfiles.handlers.StaticFilesHandler``.
* The template tags library ``adminmedia`` and the template tag ``{%
admin_media_prefix %}`` will be removed in favor of the generic static files
handling. (This is faster than the usual deprecation path; see the
:doc:`Django 1.4 release notes</releases/1.4>`.)
* The :ttag:`url` and :ttag:`ssi` template tags will be
modified so that the first argument to each tag is a template variable, not
an implied string. In 1.4, this behavior is provided by a version of the tag
in the ``future`` template tag library.
* The ``reset`` and ``sqlreset`` management commands will be removed.
* Authentication backends will need to support an inactive user
being passed to all methods dealing with permissions.
The ``supports_inactive_user`` attribute will no longer be checked
and can be removed from custom backends.
* :meth:`~django.contrib.gis.geos.GEOSGeometry.transform` will raise
a :class:`~django.contrib.gis.geos.GEOSException` when called
on a geometry with no SRID value.
* ``django.http.CompatCookie`` will be removed in favor of
``django.http.SimpleCookie``.
* ``django.core.context_processors.PermWrapper`` and
``django.core.context_processors.PermLookupDict`` will be removed in
favor of the corresponding
``django.contrib.auth.context_processors.PermWrapper`` and
``django.contrib.auth.context_processors.PermLookupDict``, respectively.
* The :setting:`MEDIA_URL` or :setting:`STATIC_URL` settings will be
required to end with a trailing slash to ensure there is a consistent
way to combine paths in templates.
* ``django.db.models.fields.URLField.verify_exists`` will be removed. The
feature was deprecated in 1.3.1 due to intractable security and
performance issues and will follow a slightly accelerated deprecation
timeframe.
* Translations located under the so-called *project path* will be ignored during
the translation building process performed at runtime. The
:setting:`LOCALE_PATHS` setting can be used for the same task by including the
filesystem path to a ``locale`` directory containing non-app-specific
translations in its value.
* The Markup contrib app will no longer support versions of Python-Markdown
library earlier than 2.1. An accelerated timeline was used as this was
a security related deprecation.
* The ``CACHE_BACKEND`` setting will be removed. The cache backend(s) should be
specified in the :setting:`CACHES` setting.
.. _deprecation-removed-in-1.4:
1.4
---
See the :ref:`Django 1.2 release notes<deprecated-features-1.2>` for more
details on these changes.
* ``CsrfResponseMiddleware`` and ``CsrfMiddleware`` will be removed. Use
the ``{% csrf_token %}`` template tag inside forms to enable CSRF
protection. ``CsrfViewMiddleware`` remains and is enabled by default.
* The old imports for CSRF functionality (``django.contrib.csrf.*``),
which moved to core in 1.2, will be removed.
* The ``django.contrib.gis.db.backend`` module will be removed in favor
of the specific backends.
* ``SMTPConnection`` will be removed in favor of a generic Email backend API.
* The many to many SQL generation functions on the database backends
will be removed.
* The ability to use the ``DATABASE_*`` family of top-level settings to
define database connections will be removed.
* The ability to use shorthand notation to specify a database backend
(i.e., ``sqlite3`` instead of ``django.db.backends.sqlite3``) will be
removed.
* The ``get_db_prep_save``, ``get_db_prep_value`` and
``get_db_prep_lookup`` methods will have to support multiple databases.
* The ``Message`` model (in ``django.contrib.auth``), its related
manager in the ``User`` model (``user.message_set``), and the
associated methods (``user.message_set.create()`` and
``user.get_and_delete_messages()``), will be removed. The
:doc:`messages framework </ref/contrib/messages>` should be used
instead. The related ``messages`` variable returned by the
auth context processor will also be removed. Note that this
means that the admin application will depend on the messages
context processor.
* Authentication backends will need to support the ``obj`` parameter for
permission checking. The ``supports_object_permissions`` attribute
will no longer be checked and can be removed from custom backends.
* Authentication backends will need to support the ``AnonymousUser`` class
being passed to all methods dealing with permissions. The
``supports_anonymous_user`` variable will no longer be checked and can be
removed from custom backends.
* The ability to specify a callable template loader rather than a
``Loader`` class will be removed, as will the ``load_template_source``
functions that are included with the built in template loaders for
backwards compatibility.
* ``django.utils.translation.get_date_formats()`` and
``django.utils.translation.get_partial_date_formats()``. These functions
will be removed; use the locale-aware
``django.utils.formats.get_format()`` to get the appropriate formats.
* In ``django.forms.fields``, the constants: ``DEFAULT_DATE_INPUT_FORMATS``,
``DEFAULT_TIME_INPUT_FORMATS`` and
``DEFAULT_DATETIME_INPUT_FORMATS`` will be removed. Use
``django.utils.formats.get_format()`` to get the appropriate
formats.
* The ability to use a function-based test runner will be removed,
along with the ``django.test.simple.run_tests()`` test runner.
* The ``views.feed()`` view and ``feeds.Feed`` class in
``django.contrib.syndication`` will be removed. The class-based view
``views.Feed`` should be used instead.
* ``django.core.context_processors.auth``. This release will
remove the old method in favor of the new method in
``django.contrib.auth.context_processors.auth``.
* The ``postgresql`` database backend will be removed, use the
``postgresql_psycopg2`` backend instead.
* The ``no`` language code will be removed and has been replaced by the
``nb`` language code.
* Authentication backends will need to define the boolean attribute
``supports_inactive_user`` until version 1.5 when it will be assumed that
all backends will handle inactive users.
* ``django.db.models.fields.XMLField`` will be removed. This was
deprecated as part of the 1.3 release. An accelerated deprecation
schedule has been used because the field hasn't performed any role
beyond that of a simple ``TextField`` since the removal of ``oldforms``.
All uses of ``XMLField`` can be replaced with ``TextField``.
* The undocumented ``mixin`` parameter to the ``open()`` method of
``django.core.files.storage.Storage`` (and subclasses) will be removed.
.. _deprecation-removed-in-1.3:
1.3
---
See the :ref:`Django 1.1 release notes<deprecated-features-1.1>` for more
details on these changes.
* ``AdminSite.root()``. This method of hooking up the admin URLs will be
removed in favor of including ``admin.site.urls``.
* Authentication backends need to define the boolean attributes
``supports_object_permissions`` and ``supports_anonymous_user`` until
version 1.4, at which point it will be assumed that all backends will
support these options.