Fix assertItemsEqual attribute error with Python 3

Summary: Fix assertItemsEqual attribute error with Python 3

Test Plan: Unit

Reviewers: matthew.auerbach, jon

Reviewed By: jon

JIRA Issues: DEV-411

Differential Revision: https://phabricator.optimizely.com/D9714

Author: Vignesh Raja

tests/test_objects.py

@@ -61,8 +61,11 @@ def test_list_equality(self):
     test_condition_list_2 = [objects.AudienceCondition('Weather', options)]
     # since __hash__ is set to None, collections.Counter comparison using memory addresses shouldn't be performed and
     # __eq__ should be called instead. Refer to: https://docs.python.org/2/reference/datamodel.html#object.__hash__
-    self.assertItemsEqual(test_condition_list_1, test_condition_list_2)
-
+    try:
+      self.assertItemsEqual(test_condition_list_1, test_condition_list_2)
+    except AttributeError:
+      # for Python 3.2+
+      self.assertCountEqual(test_condition_list_1, test_condition_list_2)
 
 class TestVisitorSet(unittest.TestCase):
   """Tests for the optimizely_platform.objects.VisitorSet class."""