code: def add_child(self, story_element_type=None, outline=None, name=None, description=None, **kwargs):
          '''
          An override of the treebeard add_child() method so we can send a signal.
          '''
          if not outline:
              outline = self.outline
          if outline != self.outline:
              raise IntegrityError('Elements must be from the same outline!')
          tree_manipulation.send(
              sender=self.__class__,
              instance=self,
              action='add_child',
              target_node_type=story_element_type,
              target_node=None,
              pos=None
          )
          return super().add_child(
              story_element_type=story_element_type,
              outline=outline,
              name=name,
              description=description,
              **kwargs
          f add_child(self, story_element_type=None, outline=None, name=None, description=None, **kwargs):
          '''
          An override of the treebeard add_child() method so we can send a signal.
          '''
          if not outline:
              outline = self.outline
          if outline != self.outline:
              raise IntegrityError('Elements must be from the same outline!')
          tree_manipulation.send(
              sender=self.__class__,
              instance=self,
              action='add_child',
              target_node_type=story_element_type,
              target_node=None,
              pos=None
          )
          return super().add_child(
              story_element_type=story_element_type,
              outline=outline,
              name=name,
              description=description,
              **kwargs
          )
docs: An override of the treebeard add_child() method so we can send a signal.