docs: def update(self, items):
          """
          Updates the dependencies in the inverse relationship format, i.e. from an iterable or dict that is structured
          as `(item, dependent_items)`. Note that this implementation is only valid for 1:1 relationships, i.e. that each
          node has also exactly one dependent. For other cases, :class:`~MultiDependencyResolver` should be used.
  
          :param items: Iterable or dictionary in the format `(item, dependent_items)`.
          :type items: collections.Iterable
          """
          for parent, sub_item in _iterate_dependencies(items):
              dep = self._deps[sub_item]
              if parent not in dep.parent:
                  dep.parent.append(parent)