diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index 804a2940a..01fe85c2b 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -1,5 +1,6 @@
 import dataclasses
 import inspect
+from collections import defaultdict
 from contextlib import contextmanager
 from copy import deepcopy
 from typing import (
@@ -17,7 +18,6 @@ from typing import (
     Union,
     cast,
 )
-from collections import defaultdict
 
 import anyio
 from fastapi import params
@@ -257,7 +257,9 @@ def is_scalar_mapping_field(field: ModelField) -> bool:
         if field.sub_fields is None:
             return True
         for sub_field in field.sub_fields:
-            if (not is_scalar_field(sub_field)) and (not is_scalar_sequence_field(sub_field)):
+            if (not is_scalar_field(sub_field)) and (
+                not is_scalar_sequence_field(sub_field)
+            ):
                 return False
         return True
     if lenient_issubclass(field.type_, mapping_types):