--- a/editors/DebugViewer.py	Fri Sep 22 20:12:22 2017 +0300
+++ b/editors/DebugViewer.py	Thu Sep 28 12:20:40 2017 +0300
@@ -35,7 +35,7 @@
 # -------------------------------------------------------------------------------
 
 
-class DebugViewer:
+class DebugViewer(object):
     """
     Class that implements common behavior of every viewers able to display debug
     values