Drop dependency on iso8601

iso8601.iso8601.UTC has been equivalent to datetime.timezone.utc in
Python 3. Because python 2 is no longer supported, we can directly use
the built-in implementation.

Change-Id: I3c2cb1b4d7ae0251cde5a54bd458aa1c80b9b783

oslo_versionedobjects/fields.py

@@ -20,7 +20,6 @@ import uuid
 import warnings
 
 import copy
-import iso8601
 import netaddr
 from oslo_utils import strutils
 from oslo_utils import timeutils
@@ -485,7 +484,7 @@ class DateTime(FieldType):
             # NOTE(danms): Legacy objects from sqlalchemy are stored in UTC,
             # but are returned without a timezone attached.
             # As a transitional aid, assume a tz-naive object is in UTC.
-            value = value.replace(tzinfo=iso8601.UTC)
+            value = value.replace(tzinfo=datetime.timezone.utc)
         elif not self.tzinfo_aware:
             value = value.replace(tzinfo=None)
         return value

oslo_versionedobjects/tests/test_fields.py

@@ -16,7 +16,6 @@ import datetime
 from unittest import mock
 import warnings
 
-import iso8601
 import netaddr
 import testtools
 
@@ -572,7 +571,7 @@ class TestFlexibleBoolean(TestField):
 class TestDateTime(TestField):
     def setUp(self):
         super().setUp()
-        self.dt = datetime.datetime(1955, 11, 5, tzinfo=iso8601.iso8601.UTC)
+        self.dt = datetime.datetime(1955, 11, 5, tzinfo=datetime.timezone.utc)
         self.field = fields.DateTimeField()
         self.coerce_good_values = [(self.dt, self.dt),
                                    (_utils.isotime(self.dt), self.dt)]
@@ -585,7 +584,7 @@ class TestDateTime(TestField):
             '1955-11-05T18:00:00Z',
             self.field.stringify(
                 datetime.datetime(1955, 11, 5, 18, 0, 0,
-                                  tzinfo=iso8601.iso8601.UTC)))
+                                  tzinfo=datetime.timezone.utc)))
 
     def test_get_schema(self):
         self.assertEqual({'type': ['string'], 'format': 'date-time',

oslo_versionedobjects/tests/test_fixture.py

@@ -18,8 +18,6 @@ import hashlib
 import inspect
 from unittest import mock
 
-import iso8601
-
 from oslo_versionedobjects import base
 from oslo_versionedobjects import exception
 from oslo_versionedobjects import fields
@@ -189,7 +187,7 @@ class TestObjectComparators(test.TestCase):
     def test_compare_obj_with_dt(self):
         mock_test = mock.Mock()
         mock_test.assertEqual = mock.Mock()
-        dt = datetime.datetime(1955, 11, 5, tzinfo=iso8601.iso8601.UTC)
+        dt = datetime.datetime(1955, 11, 5, tzinfo=datetime.timezone.utc)
         replaced_dt = dt.replace(tzinfo=None)
         my_obj = self.MyComparedObjectWithTZ(tzfield=dt)
         my_db_obj = {'tzfield': replaced_dt}

requirements.txt

@@ -8,7 +8,6 @@ oslo.context>=2.19.2 # Apache-2.0
 oslo.messaging>=5.29.0 # Apache-2.0
 oslo.serialization>=2.18.0 # Apache-2.0
 oslo.utils>=7.4.0 # Apache-2.0
-iso8601>=0.1.11 # MIT
 oslo.log>=3.36.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 WebOb>=1.7.1 # MIT