Update src/streamlit_app.py

src/streamlit_app.py

@@ -1,6 +1,6 @@
 import streamlit as st
 import zipfile, io, os
-from langchain.document_loaders import PyPDFLoader
+from langchain_community.document_loaders import PyPDFLoader
 from langchain.text_splitter import CharacterTextSplitter
 from langchain.schema import Document
 from langchain.embeddings import SentenceTransformerEmbeddings