diff --git a/development_api_navigator.py b/development_api_navigator.py
index 4bd9908cec464697f25923cd78c5bdcd0b304efd..ffd72f82fd3919e1043dcb97b688abfe6d7b379c 100644
--- a/development_api_navigator.py
+++ b/development_api_navigator.py
@@ -259,7 +259,7 @@ class ApiNavigator():
         else :
             too_long = False
         
-        __class__.generate_api_doc()
+        ApiNavigator.generate_api_doc()
         return {'FINISHED'}
 
     @staticmethod
diff --git a/development_icon_get.py b/development_icon_get.py
index 858e8a1d8f47cd3a81dc12fdd30d17a7d1886c3e..4ef58640c64ca3153d25b8a9dc62d8148f238228 100644
--- a/development_icon_get.py
+++ b/development_icon_get.py
@@ -162,8 +162,8 @@ class CONSOLE_HT_icons(bpy.types.Header):
     def draw(self, context):
         props = context.scene.icon_props
         # polling for updates
-        if props.search != __class__._search_old:
-            __class__._search_old = props.search
+        if props.search != self.__class__._search_old:
+            self.__class__._search_old = props.search
             self.icon_list = create_icon_list()
             # adjusting max value of scroller
 #            IconProps.scroll = bpy.props.IntProperty(default=1, min=1,
diff --git a/io_anim_bvh/export_bvh.py b/io_anim_bvh/export_bvh.py
index 3b70033b501eac9e28e154d225825999dd6f68d4..6ee688be6a59befdc934f7b228621a200598bd95 100644
--- a/io_anim_bvh/export_bvh.py
+++ b/io_anim_bvh/export_bvh.py
@@ -140,7 +140,7 @@ def write_armature(context,
     # redefine bones as sorted by serialized_names
     # so we can write motion
 
-    class decorated_bone(object):
+    class DecoratedBone(object):
         __slots__ = (\
         "name",  # bone name, used as key in many places
         "parent",  # decorated bone parent, set in a later loop
@@ -176,7 +176,7 @@ def write_armature(context,
             else:
                 self.rot_order_str = rotate_mode
 
-            self.rot_order = __class__._eul_order_lookup[self.rot_order_str]
+            self.rot_order = DecoratedBone._eul_order_lookup[self.rot_order_str]
 
             self.pose_mat = self.pose_bone.matrix
 
@@ -203,7 +203,7 @@ def write_armature(context,
             else:
                 return "[\"%s\" root bone]\n" % (self.name)
 
-    bones_decorated = [decorated_bone(bone_name) for bone_name in serialized_names]
+    bones_decorated = [DecoratedBone(bone_name) for bone_name in serialized_names]
 
     # Assign parents
     bones_decorated_dict = {}
diff --git a/io_anim_bvh/import_bvh.py b/io_anim_bvh/import_bvh.py
index b446085332793f594642805d308589ac4f5f4611..f8fd18e9e181af1cfdfd8ec96e99f8ccb2cd708e 100644
--- a/io_anim_bvh/import_bvh.py
+++ b/io_anim_bvh/import_bvh.py
@@ -26,10 +26,10 @@ import bpy
 from mathutils import Vector, Euler, Matrix
 
 
-class bvh_node_class(object):
+class BVH_Node(object):
     __slots__ = (
     'name',  # bvh joint name
-    'parent',  # bvh_node_class type or None for no parent
+    'parent',  # BVH_Node type or None for no parent
     'children',  # a list of children of this type.
     'rest_head_world',  # worldspace rest location for the head of this node
     'rest_head_local',  # localspace rest location for the head of this node
@@ -60,7 +60,7 @@ class bvh_node_class(object):
         self.parent = parent
         self.channels = channels
         self.rot_order = tuple(rot_order)
-        self.rot_order_str = __class__._eul_order_lookup[self.rot_order]
+        self.rot_order_str = BVH_Node._eul_order_lookup[self.rot_order]
 
         # convenience functions
         self.has_loc = channels[0] != -1 or channels[1] != -1 or channels[2] != -1
@@ -167,7 +167,7 @@ def read_bvh(context, file_path, rotate_mode='XYZ', global_scale=1.0):
             else:
                 rest_head_world = my_parent.rest_head_world + rest_head_local
 
-            bvh_node = bvh_nodes[name] = bvh_node_class(name, rest_head_world, rest_head_local, my_parent, my_channel, my_rot_order)
+            bvh_node = bvh_nodes[name] = BVH_Node(name, rest_head_world, rest_head_local, my_parent, my_channel, my_rot_order)
 
             # If we have another child then we can call ourselves a parent, else
             bvh_nodes_serial.append(bvh_node)
diff --git a/system_demo_mode/demo_mode.py b/system_demo_mode/demo_mode.py
index a2e6483940873f1193d66126661bba5a73bd4080..296abd86bfef5e0212fc02422e548a69a8ad3083 100644
--- a/system_demo_mode/demo_mode.py
+++ b/system_demo_mode/demo_mode.py
@@ -297,15 +297,15 @@ class DemoMode(bpy.types.Operator):
 
     def cleanup(self, disable=False):
         demo_mode_timer_remove()
-        __class__.first_run = True
+        DemoMode.first_run = True
 
         if disable:
-            __class__.enabled = False
+            DemoMode.enabled = False
             DemoKeepAlive.remove()
 
     def modal(self, context, event):
         # print("DemoMode.modal", global_state["anim_cycles"])
-        if not __class__.enabled:
+        if not DemoMode.enabled:
             self.cleanup(disable=True)
             return {'CANCELLED'}
 
@@ -316,8 +316,8 @@ class DemoMode(bpy.types.Operator):
             return {'CANCELLED'}
 
         # print(event.type)
-        if __class__.first_run:
-            __class__.first_run = False
+        if DemoMode.first_run:
+            DemoMode.first_run = False
 
             demo_mode_init()
         else:
@@ -336,12 +336,12 @@ class DemoMode(bpy.types.Operator):
             return {'CANCELLED'}
 
         # toggle
-        if __class__.enabled and __class__.first_run == False:
+        if DemoMode.enabled and DemoMode.first_run == False:
             # this actually cancells the previous running instance
             # should never happen now, DemoModeControl is for this.
             return {'CANCELLED'}
         else:
-            __class__.enabled = True
+            DemoMode.enabled = True
             context.window_manager.modal_handler_add(self)
 
             return {'RUNNING_MODAL'}