import gradio as gr
import os
from langchain_community.document_loaders import PYPDFloader
from langchain.txt_sliter import recursiveCharacterTextSpliter
from langchain_community.vectorstores import chroma
from langchain.chains import ConversationalRetrievalChain
from langchain_community.embeddings import HuggingFaceEmbeddings
from langchain_community.llmsimport uggingFacePipeline
from langchain.chains import ConversationChain