diff --git a/fastapi/applications.py b/fastapi/applications.py
index 02db349f1..19e3215fb 100644
--- a/fastapi/applications.py
+++ b/fastapi/applications.py
@@ -24,9 +24,9 @@ from fastapi.logger import logger
 from fastapi.middleware.asyncexitstack import AsyncExitStackMiddleware
 from fastapi.openapi.docs import (
     get_redoc_html,
+    get_stoplight_elements_html,
     get_swagger_ui_html,
     get_swagger_ui_oauth2_redirect_html,
-    get_stoplight_elements_html,
 )
 from fastapi.openapi.utils import get_openapi
 from fastapi.params import Depends
@@ -275,7 +275,11 @@ class FastAPI(Starlette):
                     openapi_url=openapi_url, title=self.title + " - Stoplight Elements"
                 )
 
-            self.add_route(self.stoplight_elements_url, stoplight_elements_html, include_in_schema=False)
+            self.add_route(
+                self.stoplight_elements_url,
+                stoplight_elements_html,
+                include_in_schema=False,
+            )
 
     async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
         if self.root_path:
diff --git a/fastapi/openapi/docs.py b/fastapi/openapi/docs.py
index d54e0c35b..ded9883dd 100644
--- a/fastapi/openapi/docs.py
+++ b/fastapi/openapi/docs.py
@@ -1,6 +1,6 @@
 import json
-from typing import Any, Dict, Optional
 from enum import Enum
+from typing import Any, Dict, Optional
 
 from fastapi.encoders import jsonable_encoder
 from starlette.responses import HTMLResponse
@@ -187,20 +187,24 @@ def get_swagger_ui_oauth2_redirect_html() -> HTMLResponse:
         """
     return HTMLResponse(content=html)
 
+
 class TryItCredentialPolicyOptions(Enum):
     OMIT = "omit"
-    include = "include"     
+    include = "include"
     SAME_ORIGIN = "same-origin"
 
+
 class LayoutOptions(Enum):
     SIDEBAR = "sidebar"
-    STACKED = "stacked"   
+    STACKED = "stacked"
+
 
 class RouterOptions(Enum):
     HISTORY = "history"
-    HASH = "hash"     
-    MEMORY = "memory"     
-    STATIC = "static"     
+    HASH = "hash"
+    MEMORY = "memory"
+    STATIC = "static"
+
 
 def get_stoplight_elements_html(
     *,