nodes = list(set(nodes))
-Mesh_1.MakeGroupByIds("nodes", SMESH.NODE, nodes)
+nodesGroup = Mesh_1.MakeGroupByIds("nodes", SMESH.NODE, nodes)
-assert(len(nodes) == 1)
+assert nodesGroup.Size() == 1, nodesGroup.GetIDs()
if salome.sg.hasDesktop():
salome.sg.updateObjBrowser(1)