Update project configuration and codebase

schemas/users.py

@@ -1,15 +1,14 @@
 from dataclasses import dataclass
-from typing import Optional
 
 
 @dataclass
 class NewUserDTO:
     id: int
-    referal: Optional[int] = None
-    link: Optional[str] = None
+    referal: int | None = None
+    link: str | None = None
 
 
 @dataclass
 class TicketCreator:
     id: int
-    username: Optional[str] = None
+    username: str | None = None