Deal with several case of steps if is defined from a DataReduction or from a tuple...

id06workflow/core/experiment/__init__.py

@@ -117,7 +117,10 @@ class Experiment(object):
         if reductionStep in (None, []):
             reductionStep = [(1, 1, 1)]
         if len(reductionStep) is 1:
-            steps = reductionStep[0].steps
+            if isinstance(reductionStep[0], DataReduction):
+                steps = reductionStep[0].steps
+            else:
+                steps = reductionStep[0]
         else:
             raise NotImplementedError('cannot manage several reduction steps for the moment')