Fixed #32528 -- Replaced django.utils.topological_sort with graphlib.TopologicalSort().

graphlib.TopologicalSort() is available since Python 3.9.

django/forms/widgets.py

@@ -6,6 +6,7 @@ import copy
 import datetime
 import warnings
 from collections import defaultdict
+from graphlib import CycleError, TopologicalSorter
 from itertools import chain
 
 from django.forms.utils import to_current_timezone
@@ -17,7 +18,6 @@ from django.utils.formats import get_format
 from django.utils.html import format_html, html_safe
 from django.utils.regex_helper import _lazy_re_compile
 from django.utils.safestring import mark_safe
-from django.utils.topological_sort import CyclicDependencyError, stable_topological_sort
 from django.utils.translation import gettext_lazy as _
 
 from .renderers import get_default_renderer
@@ -151,22 +151,22 @@ class Media:
         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)
+        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.
-            dependency_graph.setdefault(head, set())
+            ts.add(head)
             for item in list_:
                 all_items.add(item)
                 # No self dependencies
                 if head != item:
-                    dependency_graph[item].add(head)
+                    ts.add(item, head)
                 head = item
         try:
-            return stable_topological_sort(all_items, dependency_graph)
-        except CyclicDependencyError:
+            return list(ts.static_order())
+        except CycleError:
             warnings.warn(
                 "Detected duplicate Media files in an opposite order: {}".format(
                     ", ".join(repr(list_) for list_ in lists)