Update main.py

main.py

@@ -11,7 +11,8 @@ from langchain.schema import StrOutputParser
 from operator import itemgetter
 from pinecone import Pinecone
 from langchain_pinecone import PineconeVectorStore
-from langchain.memory import ChatMessageHistory, ConversationBufferMemory
+from langchain_community.chat_message_histories import ChatMessageHistory
+from langchain.memory import ConversationBufferMemory
 from langchain.schema.runnable import Runnable, RunnablePassthrough, RunnableConfig, RunnableLambda
 from langchain.callbacks.base import BaseCallbackHandler
 from langchain.chains import ConversationalRetrievalChain