          For static assets it can be important to have them included in the DOM
          in a certain order. In JavaScript you may not be able to reference a
          global or in CSS you might want to override a style.
          """
          dependency_graph = defaultdict(set)
          all_items = OrderedSet()
          for list_ in filter(None, lists):
              head = list_[0]
              # The first items depend on nothing but have to be part of the
              # dependency graph to be included in the result.
 
</s> remove             dependency_graph.setdefault(head, set())
 </s> add             ts.add(head) </s> remove             # construct a dependency graph for intra-app dependencies
            dependency_graph = {op: set() for op in ops}
 </s> add             ts = TopologicalSorter() </s> remove                                 dependency_graph[op].add(op2)

            # we use a stable sort for deterministic tests & general behavior
            self.generated_operations[app_label] = stable_topological_sort(
                ops, dependency_graph
            )
 </s> add                                 ts.add(op, op2)
            self.generated_operations[app_label] = list(ts.static_order()) </s> remove                     dependency_graph[item].add(head)
 </s> add                     ts.add(item, head)
        ts = TopologicalSorter()
          For static assets it can be important to have them included in the DOM
          in a certain order. In JavaScript you may not be able to reference a
          global or in CSS you might want to override a style.
          """
        ts = TopologicalSorter()
          all_items = OrderedSet()
          for list_ in filter(None, lists):
              head = list_[0]
              # The first items depend on nothing but have to be part of the
              # dependency graph to be included in the result.
keep keep keep keep replace keep keep keep keep keep
 Fixed #32528 -- Replaced django.utils.topological_sort with graphlib.TopologicalSort().

graphlib.TopologicalSort() is available since Python 3.9. 
django/forms/widgets.py