19-Xiang

``` from langchain_community.vectorstores import FAISS from langchain_community.vectorstores import Chroma from langchain.text_splitter import CharacterTextSplitter from langchain_community.embeddings import OpenAIEmbeddings from langchain_community.embeddings import HuggingFaceBgeEmbeddings from langchain.chains import RetrievalQA import os import openai import...