Update app.py

app.py

@@ -38,12 +38,12 @@ def invoke(openai_api_key, prompt, agent_option):
         start_time_ms = round(time.time() * 1000)
         
         if (agent_option == AGENT_LANGCHAIN):
-            result = agent_langchain(
+            completion = agent_langchain(
                 config,
                 prompt
             )
     
-            output = completion["output"]
+            result = completion["output"]
         elif (agent_option == AGENT_LLAMAINDEX):
             result = agent_llamaindex(
                 config,