Update app.py

app.py

@@ -11,6 +11,10 @@ from langchain.chains.question_answering import load_qa_chain
 from langchain.chains import LLMChain, ChatVectorDBChain
 from langchain.callbacks.base import CallbackManager
 from langchain.chains.chat_vector_db.prompts import CONDENSE_QUESTION_PROMPT as SYNTHESIS_PROMPT
+from langchain.document_loaders import DirectoryLoader
+from langchain.embeddings import OpenAIEmbeddings
+from langchain.text_splitter import RecursiveCharacterTextSplitter
+from langchain.vectorstores.faiss import FAISS
 
 
 response_prompt_template = """You are an AI assistant for the machine learning monitoring startup Arthur.  You are