Update app.py

app.py

@@ -8,7 +8,9 @@ from langchain.chains import ConversationalRetrievalChain
 from langchain_community.embeddings import HuggingFaceEmbeddings
 from langchain_community.llms import HuggingFaceEndpoint
 from langchain.memory import ConversationBufferMemory
-from langchain_community.retrievers import BM25Retriever, EnsembleRetriever  # Corrected import
+from langchain_community.retrievers import BM25Retriever
+from langchain.retrievers import EnsembleRetriever  # Try the original import (it might be in langchain.retrievers)
+
 #from langchain.chains.query_constructor.base import AttributeInfo # Removed deprecated code
 #from langchain.chains import create_query_chain # Removed deprecated code
 #from langchain.retrievers.self_query.base import SelfQueryRetriever # Removed deprecated code