Fixed #30116 -- Dropped support for Python 3.5.

INSTALL

 Thanks for downloading Django.
 
-To install it, make sure you have Python 3.5 or greater installed. Then run
+To install it, make sure you have Python 3.6 or greater installed. Then run
 this command from the command prompt:
 
     python setup.py install

django/core/checks/model_checks.py

@@ -77,10 +77,8 @@ def _check_lazy_references(apps, ignore=None):
         """
         operation, args, keywords = obj, [], {}
         while hasattr(operation, 'func'):
-            # The or clauses are redundant but work around a bug (#25945) in
-            # functools.partial in Python <= 3.5.1.
-            args.extend(getattr(operation, 'args', []) or [])
-            keywords.update(getattr(operation, 'keywords', {}) or {})
+            args.extend(getattr(operation, 'args', []))
+            keywords.update(getattr(operation, 'keywords', {}))
             operation = operation.func
         return operation, args, keywords
 

django/db/backends/base/features.py

@@ -160,10 +160,6 @@ class BaseDatabaseFeatures:
     # Support for the DISTINCT ON clause
     can_distinct_on_fields = False
 
-    # Does the backend decide to commit before SAVEPOINT statements
-    # when autocommit is disabled? https://bugs.python.org/issue8145#msg109965
-    autocommits_when_autocommit_is_off = False
-
     # Does the backend prevent running SQL queries in broken transactions?
     atomic_transactions = True
 

django/db/backends/sqlite3/features.py

-import sys
-
 from django.db.backends.base.features import BaseDatabaseFeatures
 
 from .base import Database
@@ -15,7 +13,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_timezones = False
     max_query_params = 999
     supports_mixed_date_datetime_comparisons = False
-    autocommits_when_autocommit_is_off = sys.version_info < (3, 6)
     can_introspect_autofield = True
     can_introspect_decimal_field = False
     can_introspect_duration_field = False

django/db/transaction.py

@@ -173,14 +173,6 @@ class Atomic(ContextDecorator):
             connection.commit_on_exit = True
             connection.needs_rollback = False
             if not connection.get_autocommit():
-                # sqlite3 in Python < 3.6 doesn't handle transactions and
-                # savepoints properly when autocommit is off.
-                # Turning autocommit back on isn't an option; it would trigger
-                # a premature commit. Give up if that happens.
-                if connection.features.autocommits_when_autocommit_is_off:
-                    raise TransactionManagementError(
-                        "Your database backend doesn't behave properly when "
-                        "autocommit is off. Turn it on before using 'atomic'.")
                 # Pretend we're already in an atomic block to bypass the code
                 # that disables autocommit to enter a transaction, and make a
                 # note to deal with this case in __exit__.

django/utils/functional.py

@@ -3,8 +3,6 @@ import itertools
 import operator
 from functools import total_ordering, wraps
 
-from django.utils.version import PY36, get_docs_version
-
 
 # You can't trivially replace this with `functools.partial` because this binds
 # to classes and returns bound instances, whereas functools.partial (on
@@ -22,8 +20,8 @@ class cached_property:
 
     A cached property can be made out of an existing method:
     (e.g. ``url = cached_property(get_absolute_url)``).
-    On Python < 3.6, the optional ``name`` argument must be provided, e.g.
-    ``url = cached_property(get_absolute_url, name='url')``.
+    The optional ``name`` argument is obsolete as of Python 3.6 and will be
+    deprecated in Django 4.0 (#30127).
     """
     name = None
 
@@ -34,29 +32,8 @@ class cached_property:
             '__set_name__() on it.'
         )
 
-    @staticmethod
-    def _is_mangled(name):
-        return name.startswith('__') and not name.endswith('__')
-
     def __init__(self, func, name=None):
-        if PY36:
-            self.real_func = func
-        else:
-            func_name = func.__name__
-            name = name or func_name
-            if not (isinstance(name, str) and name.isidentifier()):
-                raise ValueError(
-                    "%r can't be used as the name of a cached_property." % name,
-                )
-            if self._is_mangled(name):
-                raise ValueError(
-                    'cached_property does not work with mangled methods on '
-                    'Python < 3.6 without the appropriate `name` argument. See '
-                    'https://docs.djangoproject.com/en/%s/ref/utils/'
-                    '#cached-property-mangled-name' % get_docs_version(),
-                )
-            self.name = name
-            self.func = func
+        self.real_func = func
         self.__doc__ = getattr(func, '__doc__')
 
     def __set_name__(self, owner, name):

django/utils/module_loading.py

@@ -72,11 +72,10 @@ def module_has_submodule(package, module_name):
     full_module_name = package_name + '.' + module_name
     try:
         return importlib_find(full_module_name, package_path) is not None
-    except (ImportError, AttributeError):
-        # When module_name is an invalid dotted path, Python raises ImportError
-        # (or ModuleNotFoundError in Python 3.6+). AttributeError may be raised
+    except (ModuleNotFoundError, AttributeError):
+        # When module_name is an invalid dotted path, Python raises
+        # ModuleNotFoundError. AttributeError is raised on PY36 (fixed in PY37)
         # if the penultimate part of the path is not a package.
-        # (https://bugs.python.org/issue30436)
         return False
 
 
@@ -87,7 +86,7 @@ def module_dir(module):
     Raise ValueError otherwise, e.g. for namespace packages that are split
     over several directories.
     """
-    # Convert to list because _NamespacePath does not support indexing on 3.3.
+    # Convert to list because _NamespacePath does not support indexing.
     paths = list(getattr(module, '__path__', []))
     if len(paths) == 1:
         return paths[0]

docs/howto/windows.txt

@@ -2,7 +2,7 @@
 How to install Django on Windows
 ================================
 
-This document will guide you through installing Python 3.5 and Django on
+This document will guide you through installing Python 3.7 and Django on
 Windows. It also provides instructions for installing `virtualenv`_ and
 `virtualenvwrapper`_, which make it easier to work on Python projects. This is
 meant as a beginner's guide for users working on Django projects and does not
@@ -17,12 +17,12 @@ Install Python
 ==============
 
 Django is a Python web framework, thus requiring Python to be installed on your
-machine. At the time of writing, Python 3.5 is the latest version.
+machine. At the time of writing, Python 3.7 is the latest version.
 
 To install Python on your machine go to https://python.org/downloads/. The
 website should offer you a download button for the latest Python version.
 Download the executable installer and run it. Check the box next to ``Add
-Python 3.5 to PATH`` and then click ``Install Now``.
+Python 3.7 to PATH`` and then click ``Install Now``.
 
 After installation, open the command prompt and check that the Python version
 matches the version you installed by executing::

docs/internals/contributing/writing-code/unit-tests.txt

@@ -90,12 +90,12 @@ In addition to the default environments, ``tox`` supports running unit tests
 for other versions of Python and other database backends. Since Django's test
 suite doesn't bundle a settings file for database backends other than SQLite,
 however, you must :ref:`create and provide your own test settings
-<running-unit-tests-settings>`. For example, to run the tests on Python 3.5
+<running-unit-tests-settings>`. For example, to run the tests on Python 3.7
 using PostgreSQL::
 
-    $ tox -e py35-postgres -- --settings=my_postgres_settings
+    $ tox -e py37-postgres -- --settings=my_postgres_settings
 
-This command sets up a Python 3.5 virtual environment, installs Django's
+This command sets up a Python 3.7 virtual environment, installs Django's
 test suite dependencies (including those for PostgreSQL), and calls
 ``runtests.py`` with the supplied arguments (in this case,
 ``--settings=my_postgres_settings``).

docs/intro/reusable-apps.txt

@@ -219,8 +219,8 @@ this. For a small app like polls, this process isn't too difficult.
                'License :: OSI Approved :: BSD License',  # example license
                'Operating System :: OS Independent',
                'Programming Language :: Python',
-               'Programming Language :: Python :: 3.5',
                'Programming Language :: Python :: 3.6',
+               'Programming Language :: Python :: 3.7',
                'Topic :: Internet :: WWW/HTTP',
                'Topic :: Internet :: WWW/HTTP :: Dynamic Content',
            ],

docs/intro/tutorial01.txt

@@ -23,7 +23,7 @@ in a shell prompt (indicated by the $ prefix):
 If Django is installed, you should see the version of your installation. If it
 isn't, you'll get an error telling "No module named django".
 
-This tutorial is written for Django |version|, which supports Python 3.5 and
+This tutorial is written for Django |version|, which supports Python 3.6 and
 later. If the Django version doesn't match, you can refer to the tutorial for
 your version of Django by using the version switcher at the bottom right corner
 of this page, or update Django to the newest version. If you're using an older

docs/ref/utils.txt

@@ -514,18 +514,6 @@ https://web.archive.org/web/20110718035220/http://diveintomark.org/archives/2004
         z = person.friends         # does not call
         x is z                     # is True
 
-    .. warning::
-
-        .. _cached-property-mangled-name:
-
-        On Python < 3.6, ``cached_property`` doesn't work properly with a
-        mangled__ name unless it's passed a ``name`` of the form
-        ``_Class__attribute``::
-
-            __friends = cached_property(get_friends, name='_Person__friends')
-
-        __ https://docs.python.org/faq/programming.html#i-try-to-use-spam-and-i-get-an-error-about-someclassname-spam
-
 .. function:: keep_lazy(func, *resultclasses)
 
     Django offers many utility functions (particularly in ``django.utils``)

docs/topics/testing/tools.txt

@@ -1329,23 +1329,6 @@ The decorator can also be applied to test case classes::
     decorator. For a given class, :func:`~django.test.modify_settings` is
     always applied after :func:`~django.test.override_settings`.
 
-.. admonition:: Considerations with Python 3.5
-
-    If using Python 3.5 (or older, if using an older version of Django), avoid
-    mixing  ``remove`` with ``append`` and ``prepend`` in
-    :func:`~django.test.modify_settings`. In some cases it matters whether a
-    value is first added and then removed or vice versa, and dictionary key
-    order isn't preserved until Python 3.6. Instead, apply the decorator twice
-    to guarantee the order of operations. For example, to ensure that
-    ``SessionMiddleware`` appears first in ``MIDDLEWARE``::
-
-        @modify_settings(MIDDLEWARE={
-            'remove': ['django.contrib.sessions.middleware.SessionMiddleware'],
-        )
-        @modify_settings(MIDDLEWARE={
-            'prepend': ['django.contrib.sessions.middleware.SessionMiddleware'],
-        })
-
 .. warning::
 
     The settings file contains some settings that are only consulted during

setup.py

@@ -5,7 +5,7 @@ from distutils.sysconfig import get_python_lib
 from setuptools import find_packages, setup
 
 CURRENT_PYTHON = sys.version_info[:2]
-REQUIRED_PYTHON = (3, 5)
+REQUIRED_PYTHON = (3, 6)
 
 # This check and everything above must remain compatible with Python 2.7.
 if CURRENT_PYTHON < REQUIRED_PYTHON:
@@ -98,7 +98,6 @@ setup(
         'Operating System :: OS Independent',
         'Programming Language :: Python',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3 :: Only',

tests/admin_scripts/tests.py

@@ -32,7 +32,6 @@ from django.db.migrations.recorder import MigrationRecorder
 from django.test import (
     LiveServerTestCase, SimpleTestCase, TestCase, override_settings,
 )
-from django.utils.version import PY36
 
 custom_templates_dir = os.path.join(os.path.dirname(__file__), 'custom_templates')
 
@@ -1145,7 +1144,7 @@ class ManageCheck(AdminScriptTestCase):
         args = ['check']
         out, err = self.run_manage(args)
         self.assertNoOutput(out)
-        self.assertOutput(err, 'ModuleNotFoundError' if PY36 else 'ImportError')
+        self.assertOutput(err, 'ModuleNotFoundError')
         self.assertOutput(err, 'No module named')
         self.assertOutput(err, 'admin_scriptz')
 

tests/mail/tests.py

@@ -1211,10 +1211,7 @@ class FakeSMTPServer(smtpd.SMTPServer, threading.Thread):
 
     def __init__(self, *args, **kwargs):
         threading.Thread.__init__(self)
-        # New kwarg added in Python 3.5; default switching to False in 3.6.
-        # Setting a value only silences a deprecation warning in Python 3.5.
-        kwargs['decode_data'] = True
-        smtpd.SMTPServer.__init__(self, *args, **kwargs)
+        smtpd.SMTPServer.__init__(self, *args, decode_data=True, **kwargs)
         self._sink = []
         self.active = False
         self.active_lock = threading.Lock()

tests/migrations/test_writer.py

@@ -22,7 +22,6 @@ from django.utils.deconstruct import deconstructible
 from django.utils.functional import SimpleLazyObject
 from django.utils.timezone import get_default_timezone, get_fixed_timezone, utc
 from django.utils.translation import gettext_lazy as _
-from django.utils.version import PY36
 
 from .models import FoodManager, FoodQuerySet
 
@@ -413,10 +412,7 @@ class WriterTests(SimpleTestCase):
         # Test a string regex with flag
         validator = RegexValidator(r'^[0-9]+$', flags=re.S)
         string = MigrationWriter.serialize(validator)[0]
-        if PY36:
-            self.assertEqual(string, "django.core.validators.RegexValidator('^[0-9]+$', flags=re.RegexFlag(16))")
-        else:
-            self.assertEqual(string, "django.core.validators.RegexValidator('^[0-9]+$', flags=16)")
+        self.assertEqual(string, "django.core.validators.RegexValidator('^[0-9]+$', flags=re.RegexFlag(16))")
         self.serialize_round_trip(validator)
 
         # Test message and code

tests/model_inheritance/tests.py

-import unittest
 from operator import attrgetter
 
 from django.core.exceptions import FieldError, ValidationError
 from django.db import connection, models
 from django.test import SimpleTestCase, TestCase
 from django.test.utils import CaptureQueriesContext, isolate_apps
-from django.utils.version import PY36
 
 from .models import (
     Base, Chef, CommonInfo, GrandChild, GrandParent, ItalianRestaurant,
@@ -176,7 +174,6 @@ class ModelInheritanceTests(TestCase):
 
         self.assertIs(C._meta.parents[A], C._meta.get_field('a'))
 
-    @unittest.skipUnless(PY36, 'init_subclass is new in Python 3.6')
     @isolate_apps('model_inheritance')
     def test_init_subclass(self):
         saved_kwargs = {}
@@ -193,7 +190,6 @@ class ModelInheritanceTests(TestCase):
 
         self.assertEqual(saved_kwargs, kwargs)
 
-    @unittest.skipUnless(PY36, '__set_name__ is new in Python 3.6')
     @isolate_apps('model_inheritance')
     def test_set_name(self):
         class ClassAttr:

tests/runtests.py

@@ -234,7 +234,7 @@ def teardown(state):
     # Discard the multiprocessing.util finalizer that tries to remove a
     # temporary directory that's already removed by this script's
     # atexit.register(shutil.rmtree, TMPDIR) handler. Prevents
-    # FileNotFoundError at the end of a test run on Python 3.6+ (#27890).
+    # FileNotFoundError at the end of a test run (#27890).
     from multiprocessing.util import _finalizer_registry
     _finalizer_registry.pop((-100, 0), None)
 

tests/transactions/tests.py

@@ -228,7 +228,6 @@ class AtomicInsideTransactionTests(AtomicTests):
         self.atomic.__exit__(*sys.exc_info())
 
 
-@skipIfDBFeature('autocommits_when_autocommit_is_off')
 class AtomicWithoutAutocommitTests(AtomicTests):
     """All basic tests for atomic should also pass when autocommit is turned off."""
 
@@ -480,7 +479,6 @@ class AtomicMiscTests(TransactionTestCase):
         Reporter.objects.create()
 
 
-@skipIfDBFeature('autocommits_when_autocommit_is_off')
 class NonAutocommitTests(TransactionTestCase):
 
     available_apps = []

tests/utils_tests/test_functional.py

-import unittest
-
 from django.test import SimpleTestCase
 from django.utils.functional import cached_property, lazy
-from django.utils.version import PY36
 
 
 class FunctionalTests(SimpleTestCase):
@@ -104,7 +101,6 @@ class FunctionalTests(SimpleTestCase):
         for attr in attrs:
             self.assertCachedPropertyWorks(attr, Class)
 
-    @unittest.skipUnless(PY36, '__set_name__ is new in Python 3.6')
     def test_cached_property_auto_name(self):
         """
         cached_property caches its value and behaves like a property
@@ -132,7 +128,6 @@ class FunctionalTests(SimpleTestCase):
         obj.other2
         self.assertFalse(hasattr(obj, 'different_name'))
 
-    @unittest.skipUnless(PY36, '__set_name__ is new in Python 3.6')
     def test_cached_property_reuse_different_names(self):
         """Disallow this case because the decorated function wouldn't be cached."""
         with self.assertRaises(RuntimeError) as ctx:
@@ -151,7 +146,6 @@ class FunctionalTests(SimpleTestCase):
             ))
         )
 
-    @unittest.skipUnless(PY36, '__set_name__ is new in Python 3.6')
     def test_cached_property_reuse_same_name(self):
         """
         Reusing a cached_property on different classes under the same name is
@@ -177,7 +171,6 @@ class FunctionalTests(SimpleTestCase):
         self.assertEqual(b.cp, 2)
         self.assertEqual(a.cp, 1)
 
-    @unittest.skipUnless(PY36, '__set_name__ is new in Python 3.6')
     def test_cached_property_set_name_not_called(self):
         cp = cached_property(lambda s: None)
 
@@ -189,29 +182,6 @@ class FunctionalTests(SimpleTestCase):
         with self.assertRaisesMessage(TypeError, msg):
             Foo().cp
 
-    @unittest.skipIf(PY36, '__set_name__ is new in Python 3.6')
-    def test_cached_property_mangled_error(self):
-        msg = (
-            'cached_property does not work with mangled methods on '
-            'Python < 3.6 without the appropriate `name` argument.'
-        )
-        with self.assertRaisesMessage(ValueError, msg):
-            @cached_property
-            def __value(self):
-                pass
-        with self.assertRaisesMessage(ValueError, msg):
-            def func(self):
-                pass
-            cached_property(func, name='__value')
-
-    @unittest.skipIf(PY36, '__set_name__ is new in Python 3.6')
-    def test_cached_property_name_validation(self):
-        msg = "%s can't be used as the name of a cached_property."
-        with self.assertRaisesMessage(ValueError, msg % "'<lambda>'"):
-            cached_property(lambda x: None)
-        with self.assertRaisesMessage(ValueError, msg % 42):
-            cached_property(str, name=42)
-
     def test_lazy_equality(self):
         """
         == and != work correctly for Promises.

tests/view_tests/tests/test_debug.py

@@ -17,7 +17,6 @@ from django.test.utils import LoggingCaptureMixin
 from django.urls import path, reverse
 from django.utils.functional import SimpleLazyObject
 from django.utils.safestring import mark_safe
-from django.utils.version import PY36
 from django.views.debug import (
     CLEANSED_SUBSTITUTE, CallableSettingWrapper, ExceptionReporter,
     cleanse_setting, technical_500_response,
@@ -515,7 +514,7 @@ class ExceptionReporterTests(SimpleTestCase):
             exc_type, exc_value, tb = sys.exc_info()
         reporter = ExceptionReporter(request, exc_type, exc_value, tb)
         html = reporter.get_traceback_html()
-        self.assertInHTML('<h1>%sError at /test_view/</h1>' % ('ModuleNotFound' if PY36 else 'Import'), html)
+        self.assertInHTML('<h1>ModuleNotFoundError at /test_view/</h1>', html)
 
     def test_ignore_traceback_evaluation_exceptions(self):
         """

tox.ini

@@ -21,7 +21,7 @@ passenv = DJANGO_SETTINGS_MODULE PYTHONPATH HOME DISPLAY
 setenv =
     PYTHONDONTWRITEBYTECODE=1
 deps =
-    py{3,35,36,37}: -rtests/requirements/py3.txt
+    py{3,36,37}: -rtests/requirements/py3.txt
     postgres: -rtests/requirements/postgres.txt
     mysql: -rtests/requirements/mysql.txt
     oracle: -rtests/requirements/oracle.txt