Fixed #28909 -- Simplified code using tuple/list/set/dict unpacking.

1 files changed, 14 insertions, 18 deletions

diff --git a/django/contrib/contenttypes/admin.py b/django/contrib/contenttypes/admin.py
index dd20249e62..d1790258af 100644
--- a/django/contrib/contenttypes/admin.py
+++ b/django/contrib/contenttypes/admin.py
@@ -92,11 +92,7 @@ class GenericInlineModelAdmin(InlineModelAdmin):
             fields = kwargs.pop('fields')
         else:
             fields = flatten_fieldsets(self.get_fieldsets(request, obj))
-        if self.exclude is None:
-            exclude = []
-        else:
-            exclude = list(self.exclude)
-        exclude.extend(self.get_readonly_fields(request, obj))
+        exclude = [*(self.exclude or []), *self.get_readonly_fields(request, obj)]
         if self.exclude is None and hasattr(self.form, '_meta') and self.form._meta.exclude:
             # Take the custom ModelForm's Meta.exclude into account only if the
             # GenericInlineModelAdmin doesn't define its own.
@@ -104,20 +100,20 @@ class GenericInlineModelAdmin(InlineModelAdmin):
         exclude = exclude or None
         can_delete = self.can_delete and self.has_delete_permission(request, obj)
         defaults = {
-            "ct_field": self.ct_field,
-            "fk_field": self.ct_fk_field,
-            "form": self.form,
-            "formfield_callback": partial(self.formfield_for_dbfield, request=request),
-            "formset": self.formset,
-            "extra": self.get_extra(request, obj),
-            "can_delete": can_delete,
-            "can_order": False,
-            "fields": fields,
-            "min_num": self.get_min_num(request, obj),
-            "max_num": self.get_max_num(request, obj),
-            "exclude": exclude
+            'ct_field': self.ct_field,
+            'fk_field': self.ct_fk_field,
+            'form': self.form,
+            'formfield_callback': partial(self.formfield_for_dbfield, request=request),
+            'formset': self.formset,
+            'extra': self.get_extra(request, obj),
+            'can_delete': can_delete,
+            'can_order': False,
+            'fields': fields,
+            'min_num': self.get_min_num(request, obj),
+            'max_num': self.get_max_num(request, obj),
+            'exclude': exclude,
+            **kwargs,
         }
-        defaults.update(kwargs)
 
         if defaults['fields'] is None and not modelform_defines_fields(defaults['form']):
             defaults['fields'] = ALL_FIELDS