Update app.py

app.py

@@ -1,5 +1,7 @@
 from langchain_community.document_loaders import PyPDFLoader,DirectoryLoader
 from langchain.embeddings import HuggingFaceEmbeddings
+from langchain.embeddings.openai import OpenAIEmbeddings
+
 from langchain.text_splitter import RecursiveCharacterTextSplitter
 from langchain_community.vectorstores import FAISS
 import os