Update app.py

app.py

@@ -1,5 +1,6 @@
 from fastapi import FastAPI
 import os
+from typing import Union
 
 from custom_llm import CustomLLM
 
@@ -7,8 +8,8 @@ from pydantic import BaseModel
 from langchain.prompts import PromptTemplate
 
 class ConversationPost(BaseModel):
-    tenant: str | None = None
-    module: str | None = None
+    tenant: Union[str, None] = None
+    module: Union[str, None] = None
     question: str