added Iterator for typing

app.py

@@ -16,6 +16,8 @@ from langchain.chains import RetrievalQA
 from langchain.prompts import ChatPromptTemplate
 from langchain.document_loaders import WebBaseLoader
 
+from typing import Iterator
+
 
 text_splitter = RecursiveCharacterTextSplitter(chunk_size=350, chunk_overlap=10)
 model_id = HuggingFaceHub(repo_id="HuggingFaceH4/zephyr-7b-beta", model_kwargs={"temperature":0.1, "max_new_tokens":300})