diff --git a/stagpy/stagyydata.py b/stagpy/stagyydata.py
index <HASH>..<HASH> 100644
--- a/stagpy/stagyydata.py
+++ b/stagpy/stagyydata.py
@@ -453,7 +453,7 @@ class _EmptyStep(_Step):
         return False
 
 
-class _Steps(Mapping):
+class _Steps:
 
     """Collections of time steps.
_Steps no longer inherits Mapping

The mixin methods offered by the Mapping interface aren't relevant
to _Steps instances.