Update app.py

app.py

@@ -130,7 +130,9 @@ def main():
         embeddings = OpenAIEmbeddings()
         docsearch = Chroma.from_texts(texts, embeddings, metadatas=[{"source": str(i)} for i in range(len(texts))]).as_retriever()
         docs = docsearch.get_relevant_documents(query)
-        chain = load_qa_chain(ChatOpenAI(model = st.session_state.model_name,temperature=0), chain_type="stuff")
+	if st.session_state.model_name == 'gpt-4': max_tkns=8192
+	else : max_tkns=4096
+        chain = load_qa_chain(ChatOpenAI(model = st.session_state.model_name,max_tokens=max_tkns,temperature=0), chain_type="stuff")
         st.session_state.output = chain.run(input_documents=docs, question=query)
         #st.session_state["output"] = output
         #col3.text_area('Result', value=output, key="output_data", height=450)