code: def validate_arc_links_same_outline(sender, instance, *args, **kwargs):
      '''
      Evaluates attempts to link an arc to a story node from another outline.
      '''
      if instance.story_element_node:
          if instance.story_element_node.outline != instance.parent_outline:
              raise IntegrityError(_('An arc cannot be associated with an story element from another outline.')f validate_arc_links_same_outline(sender, instance, *args, **kwargs):
      '''
      Evaluates attempts to link an arc to a story node from another outline.
      '''
      if instance.story_element_node:
          if instance.story_element_node.outline != instance.parent_outline:
              raise IntegrityError(_('An arc cannot be associated with an story element from another outline.'))
docs: Evaluates attempts to link an arc to a story node from another outline.