code: def upsert_link_set(self, link_type, link_set):
          
          if link_set is None:
              self.links.pop(link_type, None)
              return
          links = copy.deepcopy(self.links)
          links.update({link_type: link_set})
          self.links = links
docs: Remove an item altogether by setting link_list to None.
          Currently, only links can contain multiple children of the same type.
          :param link_type:
          :param link_set:
          :return: