[lib] proper error handling during the model parsing

library/cadbiom/models/guard_transitions/translators/chart_xml.py

@@ -371,10 +371,10 @@ class MakeHandler(ContentHandler):
             try:
                 node_ori = self.node_dict[ori]
                 node_ext = self.node_dict[ext]
-            except Exception as exc:
-                print("Bad xml file - missing nodes", ori, " -> ", ext)
-                print(self.node_dict)
-                print(exc)
+            except KeyError as exc:
+                LOGGER.error("Bad xml file - missing nodes %s in %s -> %s", exc, ori, ext)
+                LOGGER.error("Nodes in memory: %s", self.node_dict)
+                raise
 
             self.current_element = self.top_pile.add_transition(node_ori, node_ext)
             # The transition may not be created (origin = ext for example)