diff --git a/docs_src/handling_errors/tutorial004.py b/docs_src/handling_errors/tutorial004.py
index b30a5001f..ee82c062c 100644
--- a/docs_src/handling_errors/tutorial004.py
+++ b/docs_src/handling_errors/tutorial004.py
@@ -1,9 +1,8 @@
-from fastapi import FastAPI, HTTPException, status, Request
+from fastapi import FastAPI, HTTPException, Request, status
+from fastapi.encoders import jsonable_encoder
 from fastapi.exceptions import RequestValidationError
-from fastapi.responses import PlainTextResponse
+from fastapi.responses import JSONResponse, PlainTextResponse
 from starlette.exceptions import HTTPException as StarletteHTTPException
-from fastapi.encoders import jsonable_encoder
-from fastapi.responses import JSONResponse
 
 app = FastAPI()
 
@@ -12,18 +11,25 @@ app = FastAPI()
 async def http_exception_handler(request, exc):
     return PlainTextResponse(str(exc.detail), status_code=exc.status_code)
 
+
 @app.exception_handler(status.HTTP_500_INTERNAL_SERVER_ERROR)
 async def internal_exception_handler(request: Request, exc: Exception):
-  return JSONResponse(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, content=jsonable_encoder({"message": "Internal Server Error"}))
+    return JSONResponse(
+        status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+        content=jsonable_encoder({"message": "Internal Server Error"}),
+    )
+
 
 @app.exception_handler(RequestValidationError)
 async def validation_exception_handler(request, exc):
     return PlainTextResponse(str(exc), status_code=400)
 
+
 @app.exception_handler(RequestValidationError)
 async def validation_exception_handler(request, exc):
     return PlainTextResponse(str(exc), status_code=400)
 
+
 @app.get("/items/{item_id}")
 async def read_item(item_id: int):
     if item_id == 3: