Update app.py

app.py

@@ -26,16 +26,6 @@ embeddings = OpenAIEmbeddings()
 vector_store = Chroma.from_documents(texts, embeddings)
 retriever = vector_store.as_retriever(search_kwargs={"k": 2})
 
-from langchain.chat_models import ChatOpenAI
-from langchain.chains import RetrievalQAWithSourcesChain
-
-llm = ChatOpenAI(model_name="gpt-3.5-turbo", temperature=0)  # Modify model_name if you have access to GPT-4
-
-chain = RetrievalQAWithSourcesChain.from_chain_type(
-    llm=llm,
-    chain_type="stuff",
-    retriever = retriever,
-    return_source_documents=True)
 
 from langchain.prompts.chat import (
     ChatPromptTemplate,