code: def fetch(self):
          
          if self.message_id is None:
              raise Exception(".message_id not set.")
          response = self.session.request("find:Message.content", [ self.message_id ])
          if response == None:
              raise Exception("Message not found.")
          self.data = response
          return self
docs: Fetch data corresponding to this draft and store it as ``self.data``.