Update conversation.py

conversation.py

@@ -1,10 +1,12 @@
 import os
 
-from langchain.embeddings import OpenAIEmbeddings
+from langchain.embeddings import OpenAIEmbeddings, HuggingFaceInstructEmbeddings
 from langchain.vectorstores import Chroma
 from langchain.chat_models import ChatOpenAI
 from langchain.chains import ConversationalRetrievalChain
 from langchain.memory import ConversationBufferMemory
+from langchain.llms import HuggingFaceHub
+
 from dotenv import load_dotenv
 load_dotenv()
 
@@ -12,10 +14,7 @@ def create_conversation() -> ConversationalRetrievalChain:
 
     persist_directory = 'db'
 
-    embeddings = OpenAIEmbeddings(
-        openai_api_key=os.getenv('OPENAI_API_KEY')
-    )
-
+    embeddings = HuggingFaceInstructEmbeddings(model_name="hkunlp/instructor-xl")
     db = Chroma(
         persist_directory=persist_directory,
         embedding_function=embeddings
@@ -27,7 +26,7 @@ def create_conversation() -> ConversationalRetrievalChain:
     )
 
     qa = ConversationalRetrievalChain.from_llm(
-        llm=ChatOpenAI(),
+        llm=HuggingFaceHub(repo_id="google/flan-t5-xxl", model_kwargs={"temperature":0.5, "max_length":512}),
         chain_type='stuff',
         retriever=db.as_retriever(),
         memory=memory,