Fixed annotations customer_service example

Author: DanieleMorotti

examples/customer_service/main.py

@@ -2,6 +2,7 @@
 
 import asyncio
 import random
+from typing import Union
 import uuid
 
 from pydantic import BaseModel
@@ -26,10 +27,10 @@
 
 
 class AirlineAgentContext(BaseModel):
-    passenger_name: str | None = None
-    confirmation_number: str | None = None
-    seat_number: str | None = None
-    flight_number: str | None = None
+    passenger_name: Union[str, None] = None
+    confirmation_number: Union[str, None] = None
+    seat_number: Union[str, None] = None
+    flight_number: Union[str, None] = None
 
 
 ### TOOLS