diff --git a/tests/test_router_circular_import.py b/tests/test_router_circular_import.py
index e4d614d56d..492a26d005 100644
--- a/tests/test_router_circular_import.py
+++ b/tests/test_router_circular_import.py
@@ -5,5 +5,8 @@ from fastapi import APIRouter
 def test_router_circular_import():
     router = APIRouter()
 
-    with pytest.raises(AssertionError, match="Cannot include the same APIRouter instance into itself. Did you mean to include a different router?"):
+    with pytest.raises(
+        AssertionError,
+        match="Cannot include the same APIRouter instance into itself. Did you mean to include a different router?",
+    ):
         router.include_router(router)