Add finalize_storages to sample code

examples/lightrag_openai_demo.py

@@ -92,6 +92,8 @@ async def initialize_rag():
 
 
 async def main():
+    rag = None
+    try:
         # Initialize RAG instance
         rag = await initialize_rag()
 
@@ -137,9 +139,15 @@ async def main():
                 "What are the top themes in this story?", param=QueryParam(mode="hybrid")
             )
         )
+    except Exception as e:
+        print(f"An error occurred: {e}")
+    finally:
+        if rag:
+            await rag.finalize_storages()
 
 
 if __name__ == "__main__":
     # Configure logging before running the main function
     configure_logging()
     asyncio.run(main())
+    print("\nDone!")