diff --git a/lib/ansible/plugins/__init__.py b/lib/ansible/plugins/__init__.py
index 14fc20fb9eb..3216a9235b2 100644
--- a/lib/ansible/plugins/__init__.py
+++ b/lib/ansible/plugins/__init__.py
@@ -31,7 +31,7 @@ import warnings
 from collections import defaultdict
 
 from ansible import constants as C
-from ansible.utils.unicode import to_str
+from ansible.utils.unicode import to_unicode
 
 try:
     from __main__ import display
@@ -248,7 +248,7 @@ class PluginLoader:
             try:
                 full_paths = (os.path.join(path, f) for f in os.listdir(path))
             except OSError as e:
-                display.warning("Error accessing plugin paths: %s" % to_str(e))
+                display.warning("Error accessing plugin paths: %s" % to_unicode(e))
 
             for full_path in (f for f in full_paths if os.path.isfile(f) and not f.endswith('__init__.py')):
                 full_name = os.path.basename(full_path)
@@ -370,7 +370,7 @@ class PluginLoader:
             try:
                 obj = getattr(self._module_cache[path], self.class_name)
             except AttributeError as e:
-                display.warning("Skipping plugin (%s) as it seems to be invalid: %s" % (path, to_str(e)))
+                display.warning("Skipping plugin (%s) as it seems to be invalid: %s" % (path, to_unicode(e)))
 
             if self.base_class:
                 # The import path is hardcoded and should be the right place,
diff --git a/lib/ansible/plugins/strategy/debug.py b/lib/ansible/plugins/strategy/debug.py
index fbfe01cbe1d..eb9ba24633e 100644
--- a/lib/ansible/plugins/strategy/debug.py
+++ b/lib/ansible/plugins/strategy/debug.py
@@ -7,7 +7,6 @@ import pprint
 import sys
 
 from ansible.plugins.strategy import linear
-from ansible.plugins.strategy import StrategyBase
 
 try:
     from __main__ import display
@@ -26,13 +25,10 @@ class NextAction(object):
         self.result = result
 
 
-class StrategyModule(linear.StrategyModule, StrategyBase):
-    # Usually inheriting linear.StrategyModule is enough. However, StrategyBase class must be
-    # direct ancestor to be considered as strategy plugin, and so we inherit the class here.
-
+class StrategyModule(linear.StrategyModule):
     def __init__(self, tqm):
         self.curr_tqm = tqm
-        StrategyBase.__init__(self, tqm)
+        super(StrategyModule, self).__init__(tqm)
 
     def _queue_task(self, host, task, task_vars, play_context):
         self.curr_host = host
@@ -40,14 +36,14 @@ class StrategyModule(linear.StrategyModule, StrategyBase):
         self.curr_task_vars = task_vars
         self.curr_play_context = play_context
 
-        StrategyBase._queue_task(self, host, task, task_vars, play_context)
+        super(StrategyModule, self)._queue_task(host, task, task_vars, play_context)
 
     def _process_pending_results(self, iterator, one_pass=False):
         if not hasattr(self, "curr_host"):
-            return StrategyBase._process_pending_results(self, iterator, one_pass)
+            return super(StrategyModule, self)._process_pending_results(iterator, one_pass)
 
         prev_host_state = iterator.get_host_state(self.curr_host)
-        results = StrategyBase._process_pending_results(self, iterator, one_pass)
+        results = super(StrategyModule, self)._process_pending_results(iterator, one_pass)
 
         while self._need_debug(results):
             next_action = NextAction()
@@ -64,8 +60,8 @@ class StrategyModule(linear.StrategyModule, StrategyBase):
                     self._tqm._stats.dark[self.curr_host.name] -= 1
 
                 # redo
-                StrategyBase._queue_task(self, self.curr_host, self.curr_task, self.curr_task_vars, self.curr_play_context)
-                results = StrategyBase._process_pending_results(self, iterator, one_pass)
+                super(StrategyModule, self)._queue_task(self.curr_host, self.curr_task, self.curr_task_vars, self.curr_play_context)
+                results = super(StrategyModule, self)._process_pending_results(iterator, one_pass)
             elif next_action.result == NextAction.CONTINUE:
                 break
             elif next_action.result == NextAction.EXIT: