Update app.py

app.py

@@ -12,7 +12,7 @@ from typing import Optional
 
 from langchain.prompts import ChatPromptTemplate, MessagesPlaceholder
 from langchain_core.chat_history import BaseChatMessageHistory
-from langchain.memory import ConversationBufferMemory, PostgresChatMessageHistory
+from langchain.memory import ConversationBufferMemory#, PostgresChatMessageHistory
 
 import psycopg2
 import urllib.parse as up