diff --git a/docs_src/handling_errors/tutorial004.py b/docs_src/handling_errors/tutorial004.py
index 8c2c3dec7..0b1c0068a 100644
--- a/docs_src/handling_errors/tutorial004.py
+++ b/docs_src/handling_errors/tutorial004.py
@@ -1,9 +1,9 @@
 from fastapi import FastAPI, HTTPException, Request
+from fastapi.encoders import jsonable_encoder
 from fastapi.exceptions import RequestValidationError
 from fastapi.responses import JSONResponse
-from starlette.exceptions import HTTPException as StarletteHTTPException
-from fastapi.encoders import jsonable_encoder
 from starlette import status
+from starlette.exceptions import HTTPException as StarletteHTTPException
 
 app = FastAPI()
 
@@ -14,10 +14,8 @@ async def http_exception_handler(request: Request, exc: StarletteHTTPException):
     Handles all HTTPException (Starlette) errors.
     Returns a JSON response with status code and detail.
     """
-    return JSONResponse(
-        status_code=exc.status_code,
-        content={"message": exc.detail}
-    )
+    return JSONResponse(status_code=exc.status_code, content={"message": exc.detail})
+
 
 @app.exception_handler(RequestValidationError)
 async def validation_exception_handler(request: Request, exc: RequestValidationError):
@@ -27,16 +25,13 @@ async def validation_exception_handler(request: Request, exc: RequestValidationE
     """
     return JSONResponse(
         status_code=status.HTTP_400_BAD_REQUEST,
-        content=jsonable_encoder({"errors": exc.errors(), "body": exc.body})
+        content=jsonable_encoder({"errors": exc.errors(), "body": exc.body}),
     )
 
 
 @app.get("/items/{item_id}")
 async def read_item(item_id: int):
-    
+
     if item_id == 3:
-        raise HTTPException(
-            status_code=418,
-            detail="Nope! I don't like 3."
-        )
+        raise HTTPException(status_code=418, detail="Nope! I don't like 3.")
     return {"item_id": item_id}