app.py

import streamlit as st
import os
from langchain_community.tools.tavily_search import TavilySearchResults
from langchain_google_community import GoogleSearchAPIWrapper
from langchain_community.utilities import GoogleSerperAPIWrapper
from langchain.tools import DuckDuckGoSearchRun, Tool
from langchain.chat_models import ChatOpenAI
from langchain.prompts import ChatPromptTemplate, MessagesPlaceholder
from langchain.agents import create_openai_tools_agent, AgentExecutor
from langgraph.graph import StateGraph, END
from langchain_core.messages import HumanMessage
from typing_extensions import TypedDict
from typing import Annotated, Sequence
import functools
import operator