pyderasn.py | 4 ++--

diff --git a/pyderasn.py b/pyderasn.py
index c21ca72a872ef9ed995d0b79a28bcafbde4055ae131d532a2cce780ed7128d7b..bb36c7d52477d47df34755cc7a48fc5b2db4d63e76f639dda71cc5506acaed2e 100755
--- a/pyderasn.py
+++ b/pyderasn.py
@@ -777,9 +777,9 @@ # Base class
 ########################################################################
 
 class AutoAddSlots(type):
-    def __new__(cls, name, bases, _dict):
+    def __new__(mcs, name, bases, _dict):
         _dict["__slots__"] = _dict.get("__slots__", ())
-        return type.__new__(cls, name, bases, _dict)
+        return type.__new__(mcs, name, bases, _dict)
 
 
 @add_metaclass(AutoAddSlots)