Update app.py

app.py

@@ -4,6 +4,8 @@ import time
 import os
 from dotenv import load_dotenv
 from sentence_transformers import SentenceTransformer
+from langchain_community.vectorstores import Chroma
+from langchain_community.embeddings import HuggingFaceEmbeddings 
 load_dotenv()
 
 CHAT_BOTS = {"Mixtral 8x7B v0.1" :"mistralai/Mixtral-8x7B-Instruct-v0.1"}