Update app.py

app.py

@@ -40,7 +40,8 @@ from langchain_core.documents import Document
 from langchain_community.document_loaders import TextLoader, PyPDFLoader
 from langchain_community.embeddings import HuggingFaceEmbeddings
 from langchain_community.llms import HuggingFaceHub
-from langchain_community.chains import RetrievalQA
+#from langchain_community.chains import RetrievalQA
+from langchain.chains import RetrievalQA  # This one might still be in main langchain
 from langchain_community.vectorstores import Chroma #from old library
 from langchain_groq import ChatGroq