Update app.py

app.py

@@ -136,7 +136,7 @@ def initialize_llmchain(temperature, max_tokens, top_k, vector_db, progress=gr.P
     progress(0.8, desc="Defining retrieval chain...")
     # qa_chain = ConversationalRetrievalChain.from_llm(llm,retriever=retriever,chain_type="stuff", 
     #                                                  memory=memory,return_source_documents=True,verbose=False)
-    qa_chain = ConversationalRetrievalChain.from_llm(llm,retriever=retriever,chain_type="map-rerank", 
+    qa_chain = ConversationalRetrievalChain.from_llm(llm,retriever=retriever,chain_type="map_rerank", 
                                                      memory=memory,return_source_documents=True,verbose=False)
     progress(0.9, desc="Done!")
     return qa_chain