diff --git a/tko/job_serializer.py b/tko/job_serializer.py
index 08b7f66..b7fa0f1 100755
--- a/tko/job_serializer.py
+++ b/tko/job_serializer.py
@@ -441,6 +441,6 @@
                 value = vartype()
             elif not isinstance(value, vartype):
                 logging.warning('Unexpected type %s for attr %s, should be %s',
-                                (type(value), attr, vartype))
+                                type(value), attr, vartype)
 
             setattr(var, attr, vartype(value))