Update app.py

app.py

@@ -6,6 +6,7 @@ import pandas as pd
 from langchain import hub
 from langchain.agents import AgentExecutor, create_react_agent
 from langchain_core.prompts import PromptTemplate
+from langchain_core.messages import HumanMessage
 from langchain_community.tools import DuckDuckGoSearchRun
 from langchain_community.llms import HuggingFaceHub
 from langchain_huggingface import HuggingFaceEndpoint, ChatHuggingFace