Update main.py

main.py

@@ -5,7 +5,7 @@ import os
 import tempfile
 import asyncio
 import time
-from typing import List, Dict, Any
+from typing import List, Dict, Any, Union
 from urllib.parse import urlparse, unquote
 from pathlib import Path
 
@@ -49,7 +49,7 @@ GROQ_MODEL_NAME = "llama3-70b-8192"
 EMBEDDING_MODEL_NAME = "sentence-transformers/all-MiniLM-L6-v2"
 
 # Global variable to hold the initialized embedding model
-embed_model_instance: HuggingFaceEmbedding | None = None
+embed_model_instance: Union[HuggingFaceEmbedding, None] = None
 
 if GROQ_API_KEY == "gsk_...":
     print("WARNING: GROQ_API_KEY is not set. Please set it in your environment or main.py.")