Update app.py

app.py

@@ -223,12 +223,13 @@ def create_chain(llm, prompt, CONDENSE_QUESTION_PROMPT, db):
     Returns:
         ConversationalRetrievalChain: The initialized conversational chain.
     """
-    memory = ConversationTokenBufferMemory(llm=llm, memory_key="chat_history", return_messages=True, input_key='question', max_token_limit=512)
+    memory = ConversationTokenBufferMemory(llm=llm, memory_key="chat_history", return_messages=True, input_key='question')
     chain = ConversationalRetrievalChain.from_llm(
         llm=llm,
         chain_type="stuff",
         retriever=db.as_retriever(search_kwargs={"k": 3}),
         return_source_documents=True,
+        max_tokens_limit=512,
         combine_docs_chain_kwargs={"prompt": prompt},
         condense_question_prompt=CONDENSE_QUESTION_PROMPT,
         memory=memory,