test if i can edit

app.py

@@ -9,7 +9,6 @@ from langchain.vectorstores import faiss
 from langchain.chat_models import ChatOpenAI
 from langchain.memory import ConversationBufferMemory
 from langchain.chains import ConversationalRetrievalChain
-from langchain.llms import HuggingFaceHub
 import os
 import pickle
 from datetime import datetime