diff --git a/tempest/lib/auth.py b/tempest/lib/auth.py
index 1857a43..83aa405 100644
--- a/tempest/lib/auth.py
+++ b/tempest/lib/auth.py
@@ -689,6 +689,10 @@
         """Credentials are equal if attributes in self.ATTRIBUTES are equal"""
         return str(self) == str(other)
 
+    def __ne__(self, other):
+        """Contrary to the __eq__"""
+        return not self.__eq__(other)
+
     def __getattr__(self, key):
         # If an attribute is set, __getattr__ is not invoked
         # If an attribute is not set, and it is a known one, return None