diff --git a/lnbits/extensions/nostrnip5/views_api.py b/lnbits/extensions/nostrnip5/views_api.py
index 23c1decf..bc4f72c7 100644
--- a/lnbits/extensions/nostrnip5/views_api.py
+++ b/lnbits/extensions/nostrnip5/views_api.py
@@ -1,6 +1,6 @@
+import re
 from http import HTTPStatus
 from typing import Optional
-import re
 
 from bech32 import bech32_decode, convertbits
 from fastapi import Query, Request, Response
@@ -159,10 +159,11 @@ async def api_address_create(
             status_code=HTTPStatus.NOT_FOUND, detail="You're sneaky, nice try."
         )
 
-    regex = re.compile(r'^[a-z0-9_.]+$')
+    regex = re.compile(r"^[a-z0-9_.]+$")
     if not re.fullmatch(regex, post_data.local_part.lower()):
         raise HTTPException(
-            status_code=HTTPStatus.NOT_FOUND, detail="Only a-z, 0-9 and .-_ are allowed characters, case insensitive."
+            status_code=HTTPStatus.NOT_FOUND,
+            detail="Only a-z, 0-9 and .-_ are allowed characters, case insensitive.",
         )
 
     exists = await get_address_by_local_part(domain_id, post_data.local_part)