Update app.py

app.py

@@ -4,6 +4,7 @@ from langchain_openai import ChatOpenAI
 from gradio import ChatMessage
 import gradio as gr
 import os
+from langchain_huggingface import ChatHuggingFace, HuggingFacePipeline
 
 from langchain_community.llms import HuggingFaceEndpoint
 from langchain_community.chat_models.huggingface import ChatHuggingFace