WIP: new way for making empty objects (sense, translation,...)

src/message/simple_edits.py

@@ -56,7 +56,7 @@ class EditExampleTranslation(Message):
     
 class AddSense(SimpleEditMessage):
     def update_model(self, model):
-        sense = self.prop
+        sense = Sense.new_empty()
         sense.labels = [self.new_text]
         model.entry.senses.append(sense)