diff --git a/spyne/util/oset.py b/spyne/util/oset.py
index 03e7c591e..e252762cf 100644
--- a/spyne/util/oset.py
+++ b/spyne/util/oset.py
@@ -1,6 +1,6 @@
 # http://code.activestate.com/recipes/576694/
 
-from spyne.util.six.moves.collections_abc import MutableSet
+from collections.abc import MutableSet
 
 KEY, PREV, NEXT = list(range(3))