use proper typing

lnbits/extensions/gerty/crud.py

@@ -50,15 +50,13 @@ async def create_gerty(wallet_id: str, data: Gerty) -> Gerty:
     return gerty
 
 
-async def update_gerty(gerty_id: str, **kwargs) -> Gerty:
+async def update_gerty(gerty_id: str, **kwargs) -> Optional[Gerty]:
     q = ", ".join([f"{field[0]} = ?" for field in kwargs.items()])
     await db.execute(
         f"UPDATE gerty.gertys SET {q} WHERE id = ?", (*kwargs.values(), gerty_id)
     )
 
-    gerty = await get_gerty(gerty_id)
-    assert gerty
-    return gerty
+    return await get_gerty(gerty_id)
 
 
 async def get_gerty(gerty_id: str) -> Optional[Gerty]:

lnbits/extensions/gerty/views_api.py

@@ -55,6 +55,9 @@ async def api_link_create_or_update(
 
         data.wallet = wallet.wallet.id
         gerty = await update_gerty(gerty_id, **data.dict())
+        assert gerty, HTTPException(
+            status_code=HTTPStatus.NOT_FOUND, detail="Gerty does not exist"
+        )
     else:
         gerty = await create_gerty(wallet_id=wallet.wallet.id, data=data)