diff --git a/st2client/tests/unit/test_commands.py b/st2client/tests/unit/test_commands.py
index b5814ebf54..cae04c2e27 100644
--- a/st2client/tests/unit/test_commands.py
+++ b/st2client/tests/unit/test_commands.py
@@ -517,7 +517,6 @@ def test_help_command_line_arg_works_for_supported_commands(self):
             # optional arguments covers both formats.
             assert isinstance(re.search("(optional arguments:|options:)", stdout), re.Match) is True
 
-
             # Verify that the actual help usage string was triggered and not the invalid
             # "too few arguments" which would indicate command doesn't actually correctly handle
             # --help flag
diff --git a/st2common/st2common/expressions/functions/version.py b/st2common/st2common/expressions/functions/version.py
index bf61c32e80..796d9289f3 100644
--- a/st2common/st2common/expressions/functions/version.py
+++ b/st2common/st2common/expressions/functions/version.py
@@ -60,4 +60,5 @@ def version_bump_patch(value):
 
 
 def version_strip_patch(value):
-    return "{major}.{minor}".format(**semver.Version.parse(value))
+    sv = semver.Version.parse(value)
+    return f"{sv.major}.{sv.minor}"
diff --git a/st2common/tests/unit/test_greenpooldispatch.py b/st2common/tests/unit/test_greenpooldispatch.py
index 4208c348b2..f77ae2937e 100644
--- a/st2common/tests/unit/test_greenpooldispatch.py
+++ b/st2common/tests/unit/test_greenpooldispatch.py
@@ -36,7 +36,7 @@ def test_dispatch_simple(self):
         call_args_list = [
             (args[0][0], args[0][1]) for args in mock_handler.call_args_list
         ]
-        self.assertItemsEqual(expected, call_args_list)
+        assert expected == call_args_list
 
     def test_dispatch_starved(self):
         dispatcher = BufferedDispatcher(
@@ -55,4 +55,4 @@ def test_dispatch_starved(self):
         call_args_list = [
             (args[0][0], args[0][1]) for args in mock_handler.call_args_list
         ]
-        self.assertItemsEqual(expected, call_args_list)
+        assert expected == call_args_list
diff --git a/st2common/tests/unit/test_model_utils_profiling.py b/st2common/tests/unit/test_model_utils_profiling.py
index db37039c80..bbdeee8c22 100644
--- a/st2common/tests/unit/test_model_utils_profiling.py
+++ b/st2common/tests/unit/test_model_utils_profiling.py
@@ -37,7 +37,7 @@ def test_logging_profiling_is_disabled(self, mock_log):
         result = log_query_and_profile_data_for_queryset(queryset=queryset)
         self.assertEqual(queryset, result)
         call_args_list = mock_log.debug.call_args_list
-        self.assertItemsEqual(call_args_list, [])
+        assert call_args_list == []
 
     @mock.patch("st2common.models.utils.profiling.LOG")
     def test_logging_profiling_is_enabled(self, mock_log):
diff --git a/st2common/tests/unit/test_util_file_system.py b/st2common/tests/unit/test_util_file_system.py
index 0dceb142a5..fa579329ae 100644
--- a/st2common/tests/unit/test_util_file_system.py
+++ b/st2common/tests/unit/test_util_file_system.py
@@ -39,8 +39,11 @@ def test_get_file_list(self):
             "meta/concurrency.yaml",
             "meta/__init__.py",
         ]
-        result = get_file_list(directory=directory, exclude_patterns=["*.pyc"])
-        self.assertItemsEqual(expected, result)
+        result = get_file_list(directory=directory, exclude_patterns=["*.pyc", "__pycache__"])
+        # directory listings are sorted because the item order must be exact for assert
+        # to validate equivalence.  Directory item order doesn't matter in general and may
+        # even change on different platforms or locales.
+        assert sorted(expected) == sorted(result)
 
         # Custom exclude pattern
         expected = [
@@ -52,4 +55,7 @@ def test_get_file_list(self):
         result = get_file_list(
             directory=directory, exclude_patterns=["*.pyc", "*.yaml", "*BUILD"]
         )
-        self.assertItemsEqual(expected, result)
+        # directory listings are sorted because the item order must be exact for assert
+        # to validate equivalence.  Directory item order doesn't matter in general and may
+        # even change on different platforms or locales.
+        assert sorted(expected) == sorted(result)
diff --git a/st2reactor/tests/unit/test_timer.py b/st2reactor/tests/unit/test_timer.py
index f4311d18d8..9ec00be5ec 100644
--- a/st2reactor/tests/unit/test_timer.py
+++ b/st2reactor/tests/unit/test_timer.py
@@ -31,8 +31,9 @@ def test_trigger_types_are_registered_on_start(self):
         timer = St2Timer()
         timer._scheduler = mock.Mock()
 
-        # Verify there are no TriggerType in the db when we start
-        self.assertItemsEqual(TriggerType.get_all(), [])
+        # Verify there are no TriggerType objects in the db when we start
+        # and cast Mongo QuerySet iterator cast to list for evaluation.
+        assert list(TriggerType.get_all()) == []
 
         timer.start()
 
@@ -55,8 +56,8 @@ def test_existing_rules_are_loaded_on_start(self):
         timer._trigger_watcher.run = mock.Mock()
 
         # Verify there are no Trigger and TriggerType in the db wh:w
-        self.assertItemsEqual(Trigger.get_all(), [])
-        self.assertItemsEqual(TriggerType.get_all(), [])
+        assert list(Trigger.get_all()) == []
+        assert list(TriggerType.get_all()) == []
 
         # Add a dummy timer Trigger object
         type_ = list(TIMER_TRIGGER_TYPES.keys())[0]