Update app.py

app.py

@@ -1,5 +1,6 @@
 import streamlit as st
-from langchain.chains import ConversationalRetrievalChain
+from streamlit_chat import message
+from langchain_community.chains import ConversationalRetrievalChain
 from langchain_community.document_loaders import PyPDFLoader, DirectoryLoader
 from langchain_community.embeddings import HuggingFaceEmbeddings
 from langchain_community.llms import CTransformers