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

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)