Fixed #27327 -- Simplified time zone handling by requiring pytz.

12 files changed, 27 insertions, 166 deletions

diff --git a/tests/admin_widgets/tests.py b/tests/admin_widgets/tests.py
index 057771bfa4..443e6c6e18 100644
--- a/tests/admin_widgets/tests.py
+++ b/tests/admin_widgets/tests.py
@@ -5,7 +5,8 @@ import gettext
 import os
 from datetime import datetime, timedelta
 from importlib import import_module
-from unittest import skipIf
+
+import pytz
 
 from django import forms
 from django.conf import settings
@@ -23,11 +24,6 @@ from django.utils import six, translation
 from . import models
 from .widgetadmin import site as widget_admin_site
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
 
 class TestDataMixin(object):
 
@@ -794,7 +790,6 @@ class DateTimePickerSeleniumTests(AdminWidgetSeleniumTestCase):
                 self.wait_for_text('#calendarin0 caption', expected_caption)
 
 
-@skipIf(pytz is None, "this test requires pytz")
 @override_settings(TIME_ZONE='Asia/Singapore')
 class DateTimePickerShortcutsSeleniumTests(AdminWidgetSeleniumTestCase):
 
diff --git a/tests/cache/tests.py b/tests/cache/tests.py
index 122017b54e..832727d53c 100644
--- a/tests/cache/tests.py
+++ b/tests/cache/tests.py
@@ -1832,17 +1832,16 @@ class CacheI18nTest(TestCase):
 
     @override_settings(USE_I18N=False, USE_L10N=False, USE_TZ=True)
     def test_cache_key_with_non_ascii_tzname(self):
-        # Regression test for #17476
-        class CustomTzName(timezone.UTC):
-            name = ''
-
-            def tzname(self, dt):
-                return self.name
+        # Timezone-dependent cache keys should use ASCII characters only
+        # (#17476). The implementation here is a bit odd (timezone.utc is an
+        # instance, not a class), but it simulates the correct conditions.
+        class CustomTzName(timezone.utc):
+            pass
 
         request = self.factory.get(self.path)
         response = HttpResponse()
-        with timezone.override(CustomTzName()):
-            CustomTzName.name = 'Hora estándar de Argentina'.encode('UTF-8')  # UTF-8 string
+        with timezone.override(CustomTzName):
+            CustomTzName.zone = 'Hora estándar de Argentina'.encode('UTF-8')  # UTF-8 string
             sanitized_name = 'Hora_estndar_de_Argentina'
             self.assertIn(
                 sanitized_name, learn_cache_key(request, response),
diff --git a/tests/datetimes/tests.py b/tests/datetimes/tests.py
index efef456c43..273333e61c 100644
--- a/tests/datetimes/tests.py
+++ b/tests/datetimes/tests.py
@@ -1,18 +1,12 @@
 from __future__ import unicode_literals
 
 import datetime
-from unittest import skipIf
 
 from django.test import TestCase, override_settings
 from django.utils import timezone
 
 from .models import Article, Category, Comment
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
 
 class DateTimesTests(TestCase):
     def test_related_model_traverse(self):
@@ -84,7 +78,6 @@ class DateTimesTests(TestCase):
             ],
         )
 
-    @skipIf(pytz is None, "this test requires pytz")
     @override_settings(USE_TZ=True)
     def test_21432(self):
         now = timezone.localtime(timezone.now().replace(microsecond=0))
diff --git a/tests/db_functions/test_datetime.py b/tests/db_functions/test_datetime.py
index 1b44c9a658..f9a9a54c1c 100644
--- a/tests/db_functions/test_datetime.py
+++ b/tests/db_functions/test_datetime.py
@@ -1,7 +1,8 @@
 from __future__ import unicode_literals
 
 from datetime import datetime
-from unittest import skipIf
+
+import pytz
 
 from django.conf import settings
 from django.db import connection
@@ -16,11 +17,6 @@ from django.utils import timezone
 
 from .models import DTModel
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
 
 def microsecond_support(value):
     return value if connection.features.supports_microsecond_precision else value.replace(microsecond=0)
@@ -659,7 +655,6 @@ class DateFunctionTests(TestCase):
             list(DTModel.objects.annotate(truncated=TruncSecond('start_date', output_field=DateField())))
 
 
-@skipIf(pytz is None, "this test requires pytz")
 @override_settings(USE_TZ=True, TIME_ZONE='UTC')
 class DateFunctionWithTimeZoneTests(DateFunctionTests):
 
diff --git a/tests/file_storage/tests.py b/tests/file_storage/tests.py
index acb663ef7a..5492f105f7 100644
--- a/tests/file_storage/tests.py
+++ b/tests/file_storage/tests.py
@@ -32,12 +32,6 @@ from django.utils.six.moves.urllib.request import urlopen
 
 from .models import Storage, temp_storage, temp_storage_location
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
-
 FILE_SUFFIX_REGEX = '[A-Za-z0-9]{7}'
 
 
@@ -99,10 +93,6 @@ class FileSystemStorageTests(unittest.TestCase):
             storage.url(storage.base_url)
 
 
-# Tests for TZ-aware time methods need pytz.
-requires_pytz = unittest.skipIf(pytz is None, "this test requires pytz")
-
-
 class FileStorageTests(SimpleTestCase):
     storage_class = FileSystemStorage
 
@@ -157,7 +147,6 @@ class FileStorageTests(SimpleTestCase):
         # different.
         now_in_algiers = timezone.make_aware(datetime.now())
 
-        # Use a fixed offset timezone so we don't need pytz.
         with timezone.override(timezone.get_fixed_timezone(-300)):
             # At this point the system TZ is +1 and the Django TZ
             # is -5. The following will be aware in UTC.
@@ -191,7 +180,6 @@ class FileStorageTests(SimpleTestCase):
         # different.
         now_in_algiers = timezone.make_aware(datetime.now())
 
-        # Use a fixed offset timezone so we don't need pytz.
         with timezone.override(timezone.get_fixed_timezone(-300)):
             # At this point the system TZ is +1 and the Django TZ
             # is -5.
@@ -220,7 +208,6 @@ class FileStorageTests(SimpleTestCase):
             _dt = timezone.make_aware(dt, now_in_algiers.tzinfo)
             self.assertLess(abs(_dt - now_in_algiers), timedelta(seconds=2))
 
-    @requires_pytz
     def test_file_get_accessed_time(self):
         """
         File storage returns a Datetime object for the last accessed time of
@@ -236,7 +223,6 @@ class FileStorageTests(SimpleTestCase):
         self.assertEqual(atime, datetime.fromtimestamp(os.path.getatime(self.storage.path(f_name))))
         self.assertLess(timezone.now() - self.storage.get_accessed_time(f_name), timedelta(seconds=2))
 
-    @requires_pytz
     @requires_tz_support
     def test_file_get_accessed_time_timezone(self):
         self._test_file_time_getter(self.storage.get_accessed_time)
@@ -256,7 +242,6 @@ class FileStorageTests(SimpleTestCase):
         self.assertEqual(atime, datetime.fromtimestamp(os.path.getatime(self.storage.path(f_name))))
         self.assertLess(datetime.now() - self.storage.accessed_time(f_name), timedelta(seconds=2))
 
-    @requires_pytz
     def test_file_get_created_time(self):
         """
         File storage returns a datetime for the creation time of a file.
@@ -271,7 +256,6 @@ class FileStorageTests(SimpleTestCase):
         self.assertEqual(ctime, datetime.fromtimestamp(os.path.getctime(self.storage.path(f_name))))
         self.assertLess(timezone.now() - self.storage.get_created_time(f_name), timedelta(seconds=2))
 
-    @requires_pytz
     @requires_tz_support
     def test_file_get_created_time_timezone(self):
         self._test_file_time_getter(self.storage.get_created_time)
@@ -291,7 +275,6 @@ class FileStorageTests(SimpleTestCase):
         self.assertEqual(ctime, datetime.fromtimestamp(os.path.getctime(self.storage.path(f_name))))
         self.assertLess(datetime.now() - self.storage.created_time(f_name), timedelta(seconds=2))
 
-    @requires_pytz
     def test_file_get_modified_time(self):
         """
         File storage returns a datetime for the last modified time of a file.
@@ -306,7 +289,6 @@ class FileStorageTests(SimpleTestCase):
         self.assertEqual(mtime, datetime.fromtimestamp(os.path.getmtime(self.storage.path(f_name))))
         self.assertLess(timezone.now() - self.storage.get_modified_time(f_name), timedelta(seconds=2))
 
-    @requires_pytz
     @requires_tz_support
     def test_file_get_modified_time_timezone(self):
         self._test_file_time_getter(self.storage.get_modified_time)
diff --git a/tests/humanize_tests/tests.py b/tests/humanize_tests/tests.py
index 22ae426954..a3cc512239 100644
--- a/tests/humanize_tests/tests.py
+++ b/tests/humanize_tests/tests.py
@@ -2,7 +2,6 @@ from __future__ import unicode_literals
 
 import datetime
 from decimal import Decimal
-from unittest import skipIf
 
 from django.contrib.humanize.templatetags import humanize
 from django.template import Context, Template, defaultfilters
@@ -12,12 +11,6 @@ from django.utils.html import escape
 from django.utils.timezone import get_fixed_timezone, utc
 from django.utils.translation import ugettext as _
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
-
 # Mock out datetime in some tests so they don't fail occasionally when they
 # run too slow. Use a fixed datetime for datetime.now(). DST change in
 # America/Chicago (the default time zone) happened on March 11th in 2012.
@@ -174,7 +167,6 @@ class HumanizeTests(SimpleTestCase):
         # As 24h of difference they will never be the same
         self.assertNotEqual(naturalday_one, naturalday_two)
 
-    @skipIf(pytz is None, "this test requires pytz")
     def test_naturalday_uses_localtime(self):
         # Regression for #18504
         # This is 2012-03-08HT19:30:00-06:00 in America/Chicago
diff --git a/tests/requirements/base.txt b/tests/requirements/base.txt
index 374b836fad..f9cb570c62 100644
--- a/tests/requirements/base.txt
+++ b/tests/requirements/base.txt
@@ -8,7 +8,6 @@ Pillow
 PyYAML
 # pylibmc/libmemcached can't be built on Windows.
 pylibmc; sys.platform != 'win32'
-pytz > dev
 selenium
 sqlparse
 tblib
diff --git a/tests/schema/tests.py b/tests/schema/tests.py
index 9aeada3e67..567a1f86da 100644
--- a/tests/schema/tests.py
+++ b/tests/schema/tests.py
@@ -22,7 +22,7 @@ from django.test import (
     TransactionTestCase, mock, skipIfDBFeature, skipUnlessDBFeature,
 )
 from django.test.utils import CaptureQueriesContext
-from django.utils.timezone import UTC
+from django.utils import timezone
 
 from .fields import (
     CustomManyToManyField, InheritedManyToManyField, MediumBlobField,
@@ -2187,7 +2187,7 @@ class SchemaTests(TransactionTestCase):
         TimeField if auto_now or auto_add_now is set (#25005).
         """
         now = datetime.datetime(month=1, day=1, year=2000, hour=1, minute=1)
-        now_tz = datetime.datetime(month=1, day=1, year=2000, hour=1, minute=1, tzinfo=UTC())
+        now_tz = datetime.datetime(month=1, day=1, year=2000, hour=1, minute=1, tzinfo=timezone.utc)
         mocked_datetime.now = mock.MagicMock(return_value=now)
         mocked_tz.now = mock.MagicMock(return_value=now_tz)
         # Create the table
diff --git a/tests/syndication_tests/tests.py b/tests/syndication_tests/tests.py
index 6f4655838a..60285efea7 100644
--- a/tests/syndication_tests/tests.py
+++ b/tests/syndication_tests/tests.py
@@ -16,11 +16,6 @@ from django.utils.feedgenerator import (
 
 from .models import Article, Entry
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
 TZ = timezone.get_default_timezone()
 
 
diff --git a/tests/timezones/tests.py b/tests/timezones/tests.py
index e72fff069b..d95877d227 100644
--- a/tests/timezones/tests.py
+++ b/tests/timezones/tests.py
@@ -8,6 +8,8 @@ from contextlib import contextmanager
 from unittest import SkipTest, skipIf
 from xml.dom.minidom import parseString
 
+import pytz
+
 from django.contrib.auth.models import User
 from django.core import serializers
 from django.core.exceptions import ImproperlyConfigured
@@ -33,13 +35,6 @@ from .models import (
     AllDayEvent, Event, MaybeEvent, Session, SessionEvent, Timestamp,
 )
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
-requires_pytz = skipIf(pytz is None, "this test requires pytz")
-
 # These tests use the EAT (Eastern Africa Time) and ICT (Indochina Time)
 # who don't have Daylight Saving Time, so we can represent them easily
 # with FixedOffset, and use them directly as tzinfo in the constructors.
@@ -363,7 +358,6 @@ class NewDatabaseTests(TestCase):
         self.assertEqual(Event.objects.filter(dt__gte=dt2).count(), 1)
         self.assertEqual(Event.objects.filter(dt__gt=dt2).count(), 0)
 
-    @requires_pytz
     def test_query_filter_with_pytz_timezones(self):
         tz = pytz.timezone('Europe/Paris')
         dt = datetime.datetime(2011, 9, 1, 12, 20, 30, tzinfo=tz)
@@ -908,7 +902,6 @@ class TemplateTests(SimpleTestCase):
                     expected = results[k1][k2]
                     self.assertEqual(actual, expected, '%s / %s: %r != %r' % (k1, k2, actual, expected))
 
-    @requires_pytz
     def test_localtime_filters_with_pytz(self):
         """
         Test the |localtime, |utc, and |timezone filters with pytz.
@@ -976,7 +969,6 @@ class TemplateTests(SimpleTestCase):
             "2011-09-01T13:20:30+03:00|2011-09-01T17:20:30+07:00|2011-09-01T13:20:30+03:00"
         )
 
-    @requires_pytz
     def test_timezone_templatetag_with_pytz(self):
         """
         Test the {% timezone %} templatetag with pytz.
@@ -996,7 +988,7 @@ class TemplateTests(SimpleTestCase):
     def test_timezone_templatetag_invalid_argument(self):
         with self.assertRaises(TemplateSyntaxError):
             Template("{% load tz %}{% timezone %}{% endtimezone %}").render()
-        with self.assertRaises(ValueError if pytz is None else pytz.UnknownTimeZoneError):
+        with self.assertRaises(pytz.UnknownTimeZoneError):
             Template("{% load tz %}{% timezone tz %}{% endtimezone %}").render(Context({'tz': 'foobar'}))
 
     @skipIf(sys.platform.startswith('win'), "Windows uses non-standard time zone names")
@@ -1006,7 +998,7 @@ class TemplateTests(SimpleTestCase):
         """
         tpl = Template("{% load tz %}{% get_current_timezone as time_zone %}{{ time_zone }}")
 
-        self.assertEqual(tpl.render(Context()), "Africa/Nairobi" if pytz else "EAT")
+        self.assertEqual(tpl.render(Context()), "Africa/Nairobi")
         with timezone.override(UTC):
             self.assertEqual(tpl.render(Context()), "UTC")
 
@@ -1019,7 +1011,6 @@ class TemplateTests(SimpleTestCase):
         with timezone.override(UTC):
             self.assertEqual(tpl.render(Context({'tz': ICT})), "+0700")
 
-    @requires_pytz
     def test_get_current_timezone_templatetag_with_pytz(self):
         """
         Test the {% get_current_timezone %} templatetag with pytz.
@@ -1048,7 +1039,7 @@ class TemplateTests(SimpleTestCase):
         context = Context()
         self.assertEqual(tpl.render(context), "")
         request_context = RequestContext(HttpRequest(), processors=[context_processors.tz])
-        self.assertEqual(tpl.render(request_context), "Africa/Nairobi" if pytz else "EAT")
+        self.assertEqual(tpl.render(request_context), "Africa/Nairobi")
 
     @requires_tz_support
     def test_date_and_time_template_filters(self):
@@ -1068,15 +1059,6 @@ class TemplateTests(SimpleTestCase):
         with timezone.override(ICT):
             self.assertEqual(tpl.render(ctx), "2011-09-01 at 20:20:20")
 
-    def test_localtime_with_time_zone_setting_set_to_none(self):
-        # Regression for #17274
-        tpl = Template("{% load tz %}{{ dt }}")
-        ctx = Context({'dt': datetime.datetime(2011, 9, 1, 12, 20, 30, tzinfo=EAT)})
-
-        with self.settings(TIME_ZONE=None):
-            # the actual value depends on the system time zone of the host
-            self.assertTrue(tpl.render(ctx).startswith("2011"))
-
     @requires_tz_support
     def test_now_template_tag_uses_current_time_zone(self):
         # Regression for #17343
@@ -1094,7 +1076,6 @@ class LegacyFormsTests(TestCase):
         self.assertTrue(form.is_valid())
         self.assertEqual(form.cleaned_data['dt'], datetime.datetime(2011, 9, 1, 13, 20, 30))
 
-    @requires_pytz
     def test_form_with_non_existent_time(self):
         form = EventForm({'dt': '2011-03-27 02:30:00'})
         with timezone.override(pytz.timezone('Europe/Paris')):
@@ -1102,7 +1083,6 @@ class LegacyFormsTests(TestCase):
             self.assertTrue(form.is_valid())
             self.assertEqual(form.cleaned_data['dt'], datetime.datetime(2011, 3, 27, 2, 30, 0))
 
-    @requires_pytz
     def test_form_with_ambiguous_time(self):
         form = EventForm({'dt': '2011-10-30 02:30:00'})
         with timezone.override(pytz.timezone('Europe/Paris')):
@@ -1141,7 +1121,6 @@ class NewFormsTests(TestCase):
         # Datetime inputs formats don't allow providing a time zone.
         self.assertFalse(form.is_valid())
 
-    @requires_pytz
     def test_form_with_non_existent_time(self):
         with timezone.override(pytz.timezone('Europe/Paris')):
             form = EventForm({'dt': '2011-03-27 02:30:00'})
@@ -1153,7 +1132,6 @@ class NewFormsTests(TestCase):
                 ]
             )
 
-    @requires_pytz
     def test_form_with_ambiguous_time(self):
         with timezone.override(pytz.timezone('Europe/Paris')):
             form = EventForm({'dt': '2011-10-30 02:30:00'})
diff --git a/tests/utils_tests/test_dateformat.py b/tests/utils_tests/test_dateformat.py
index bda69fb4cd..bd99b31a42 100644
--- a/tests/utils_tests/test_dateformat.py
+++ b/tests/utils_tests/test_dateformat.py
@@ -1,8 +1,6 @@
 from __future__ import unicode_literals
 
-import sys
 from datetime import date, datetime
-from unittest import skipIf
 
 from django.test import SimpleTestCase, override_settings
 from django.test.utils import TZ_SUPPORT, requires_tz_support
@@ -12,11 +10,6 @@ from django.utils.timezone import (
     get_default_timezone, get_fixed_timezone, make_aware, utc,
 )
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
 
 @override_settings(TIME_ZONE='Europe/Copenhagen')
 class DateFormatTests(SimpleTestCase):
@@ -36,18 +29,16 @@ class DateFormatTests(SimpleTestCase):
         dt = datetime(2009, 5, 16, 5, 30, 30)
         self.assertEqual(datetime.fromtimestamp(int(format(dt, 'U'))), dt)
 
-    @skipIf(sys.platform.startswith('win') and not pytz, "Test requires pytz on Windows")
     def test_naive_ambiguous_datetime(self):
-        # dt is ambiguous in Europe/Copenhagen. LocalTimezone guesses the
-        # offset (and gets it wrong 50% of the time) while pytz refuses the
-        # temptation to guess. In any case, this shouldn't crash.
+        # dt is ambiguous in Europe/Copenhagen. pytz raises an exception for
+        # the ambiguity, which results in an empty string.
         dt = datetime(2015, 10, 25, 2, 30, 0)
 
         # Try all formatters that involve self.timezone.
-        self.assertEqual(format(dt, 'I'), '0' if pytz is None else '')
-        self.assertEqual(format(dt, 'O'), '+0100' if pytz is None else '')
-        self.assertEqual(format(dt, 'T'), 'CET' if pytz is None else '')
-        self.assertEqual(format(dt, 'Z'), '3600' if pytz is None else '')
+        self.assertEqual(format(dt, 'I'), '')
+        self.assertEqual(format(dt, 'O'), '')
+        self.assertEqual(format(dt, 'T'), '')
+        self.assertEqual(format(dt, 'Z'), '')
 
     @requires_tz_support
     def test_datetime_with_local_tzinfo(self):
diff --git a/tests/utils_tests/test_timezone.py b/tests/utils_tests/test_timezone.py
index 1be1d63b2c..2fe5445c48 100644
--- a/tests/utils_tests/test_timezone.py
+++ b/tests/utils_tests/test_timezone.py
@@ -1,21 +1,12 @@
-import copy
 import datetime
-import pickle
 import sys
-import unittest
+
+import pytz
 
 from django.test import SimpleTestCase, mock, override_settings
 from django.utils import timezone
 
-try:
-    import pytz
-except ImportError:
-    pytz = None
-
-requires_pytz = unittest.skipIf(pytz is None, "this test requires pytz")
-
-if pytz is not None:
-    CET = pytz.timezone("Europe/Paris")
+CET = pytz.timezone("Europe/Paris")
 EAT = timezone.get_fixed_timezone(180)      # Africa/Nairobi
 ICT = timezone.get_fixed_timezone(420)      # Asia/Bangkok
 
@@ -24,33 +15,6 @@ PY36 = sys.version_info >= (3, 6)
 
 class TimezoneTests(SimpleTestCase):
 
-    def test_localtime(self):
-        now = datetime.datetime.utcnow().replace(tzinfo=timezone.utc)
-        local_tz = timezone.LocalTimezone()
-        with timezone.override(local_tz):
-            local_now = timezone.localtime(now)
-            self.assertEqual(local_now.tzinfo, local_tz)
-        local_now = timezone.localtime(now, timezone=local_tz)
-        self.assertEqual(local_now.tzinfo, local_tz)
-
-    def test_localtime_naive(self):
-        now = datetime.datetime.now()
-        if PY36:
-            self.assertEqual(timezone.localtime(now), now.replace(tzinfo=timezone.LocalTimezone()))
-        else:
-            with self.assertRaisesMessage(ValueError, 'astimezone() cannot be applied to a naive datetime'):
-                timezone.localtime(now)
-
-    def test_localtime_out_of_range(self):
-        local_tz = timezone.LocalTimezone()
-        long_ago = datetime.datetime(1900, 1, 1, tzinfo=timezone.utc)
-        try:
-            timezone.localtime(long_ago, local_tz)
-        except (OverflowError, ValueError) as exc:
-            self.assertIn("install pytz", exc.args[0])
-        else:
-            self.skipTest("Failed to trigger an OverflowError or ValueError")
-
     def test_now(self):
         with override_settings(USE_TZ=True):
             self.assertTrue(timezone.is_aware(timezone.now()))
@@ -133,18 +97,6 @@ class TimezoneTests(SimpleTestCase):
         finally:
             timezone.deactivate()
 
-    def test_copy(self):
-        self.assertIsInstance(copy.copy(timezone.UTC()), timezone.UTC)
-        self.assertIsInstance(copy.copy(timezone.LocalTimezone()), timezone.LocalTimezone)
-
-    def test_deepcopy(self):
-        self.assertIsInstance(copy.deepcopy(timezone.UTC()), timezone.UTC)
-        self.assertIsInstance(copy.deepcopy(timezone.LocalTimezone()), timezone.LocalTimezone)
-
-    def test_pickling_unpickling(self):
-        self.assertIsInstance(pickle.loads(pickle.dumps(timezone.UTC())), timezone.UTC)
-        self.assertIsInstance(pickle.loads(pickle.dumps(timezone.LocalTimezone())), timezone.LocalTimezone)
-
     def test_is_aware(self):
         self.assertTrue(timezone.is_aware(datetime.datetime(2011, 9, 1, 13, 20, 30, tzinfo=EAT)))
         self.assertFalse(timezone.is_aware(datetime.datetime(2011, 9, 1, 13, 20, 30)))
@@ -175,7 +127,6 @@ class TimezoneTests(SimpleTestCase):
             with self.assertRaisesMessage(ValueError, 'astimezone() cannot be applied to a naive datetime'):
                 timezone.make_naive(*args)
 
-    @requires_pytz
     def test_make_aware2(self):
         self.assertEqual(
             timezone.make_aware(datetime.datetime(2011, 9, 1, 12, 20, 30), CET),
@@ -183,7 +134,6 @@ class TimezoneTests(SimpleTestCase):
         with self.assertRaises(ValueError):
             timezone.make_aware(CET.localize(datetime.datetime(2011, 9, 1, 12, 20, 30)), CET)
 
-    @requires_pytz
     def test_make_aware_pytz(self):
         self.assertEqual(
             timezone.make_naive(CET.localize(datetime.datetime(2011, 9, 1, 12, 20, 30)), CET),
@@ -202,7 +152,6 @@ class TimezoneTests(SimpleTestCase):
             with self.assertRaises(ValueError):
                 timezone.make_naive(datetime.datetime(2011, 9, 1, 12, 20, 30), CET)
 
-    @requires_pytz
     def test_make_aware_pytz_ambiguous(self):
         # 2:30 happens twice, once before DST ends and once after
         ambiguous = datetime.datetime(2015, 10, 25, 2, 30)
@@ -216,7 +165,6 @@ class TimezoneTests(SimpleTestCase):
         self.assertEqual(std.tzinfo.utcoffset(std), datetime.timedelta(hours=1))
         self.assertEqual(dst.tzinfo.utcoffset(dst), datetime.timedelta(hours=2))
 
-    @requires_pytz
     def test_make_aware_pytz_non_existent(self):
         # 2:30 never happened due to DST
         non_existent = datetime.datetime(2015, 3, 29, 2, 30)
@@ -229,9 +177,3 @@ class TimezoneTests(SimpleTestCase):
         self.assertEqual(std - dst, datetime.timedelta(hours=1))
         self.assertEqual(std.tzinfo.utcoffset(std), datetime.timedelta(hours=1))
         self.assertEqual(dst.tzinfo.utcoffset(dst), datetime.timedelta(hours=2))
-
-        # round trip to UTC then back to CET
-        std = timezone.localtime(timezone.localtime(std, timezone.UTC()), CET)
-        dst = timezone.localtime(timezone.localtime(dst, timezone.UTC()), CET)
-        self.assertEqual((std.hour, std.minute), (3, 30))
-        self.assertEqual((dst.hour, dst.minute), (1, 30))