Update app.py

app.py

@@ -33,7 +33,7 @@ def pdf_changes(pdf_doc, open_ai_key):
         qa = ConversationalRetrievalChain.from_llm(
             llm=OpenAI(temperature=0.5), 
             retriever=retriever, 
-            return_source_documents=True)
+            return_source_documents=False) # if you set this to True, you will not get a response due to a silent error.
         return "Ready"
     else:
         return "You forgot OpenAI API key"