fix log output

ml/dt_factory.py

@@ -193,11 +193,12 @@ def build_sub_features(feature_ins, feature):
         sub_f_name = sub_f.get("name")
         if sub_f_name is None:
             sub_f_name = sub_f.get("class", "")
-        sub_f_obj = DT_FACTORY.get(remove_namespace(sub_f.get("class", "")), None)
+        _class_name = sub_f.get("class", "")
+        sub_f_obj = DT_FACTORY.get(remove_namespace(_class_name), None)
         if sub_f_obj is None:
-            APP_LOGGER.critical("Subfeature: %s is missing" % sub_f_name)
+            APP_LOGGER.critical("Subfeature: %s is missing" % _class_name)
         else:
-            APP_LOGGER.info("Adding subfeature: %s" % sub_f_name)
+            APP_LOGGER.info("Adding subfeature: %s" % _class_name)
             sub_f_instance = sub_f_obj()
             for key in sub_f.keys():
                 if key == "targets":