Update chain.py

chain.py

@@ -9,6 +9,7 @@ from langchain.embeddings import OpenAIEmbeddings
 ## deprectated from langchain.vectorstores import Chroma
 from langchain_community.vectorstores import Chroma
 from prompts import load_chat_prompt
+import pathlib
 
 
 logger = logging.getLogger(__name__)