Learn how to Construct Human-in-the-Loop Plan-and-Execute AI Brokers with Express Consumer Approval Utilizing LangGraph and Streamlit

app_code = r'''
import os, json, uuid
import streamlit as st
from typing import TypedDict, Checklist, Dict, Any, Non-obligatory
from pydantic import BaseModel, Area
from openai import OpenAI


from langgraph.graph import StateGraph, START, END
from langgraph.sorts import Command, interrupt
from langgraph.checkpoint.reminiscence import InMemorySaver




def tool_search_flights(origin: str, vacation spot: str, depart_date: str, return_date: str, budget_usd: int) -> Dict[str, Any]:
   choices = [
       {"airline": "SkyJet", "route": f"{origin}->{destination}", "depart": depart_date, "return": return_date, "price_usd": int(budget_usd*0.55)},
       {"airline": "AeroBlue", "route": f"{origin}->{destination}", "depart": depart_date, "return": return_date, "price_usd": int(budget_usd*0.70)},
       {"airline": "Nimbus Air", "route": f"{origin}->{destination}", "depart": depart_date, "return": return_date, "price_usd": int(budget_usd*0.62)},
   ]
   choices = sorted(choices, key=lambda x: x["price_usd"])
   return {"device": "search_flights", "top_options": choices[:2]}


def tool_search_hotels(metropolis: str, nights: int, budget_usd: int, preferences: Checklist[str]) -> Dict[str, Any]:
   base = max(60, int(budget_usd / max(nights, 1)))
   picks = [
       {"name": "Central Boutique", "city": city, "nightly_usd": int(base*0.95), "notes": ["walkable", "great reviews"]},
       {"identify": "Riverside Keep", "metropolis": metropolis, "nightly_usd": int(base*0.80), "notes": ["quiet", "good value"]},
       {"identify": "Trendy Loft Lodge", "metropolis": metropolis, "nightly_usd": int(base*1.10), "notes": ["new", "gym"]},
   ]
   if "luxurious" in [p.lower() for p in preferences]:
       picks = sorted(picks, key=lambda x: -x["nightly_usd"])
   else:
       picks = sorted(picks, key=lambda x: x["nightly_usd"])
   return {"device": "search_hotels", "top_options": picks[:2]}


def tool_build_day_by_day(metropolis: str, days: int, vibe: str) -> Dict[str, Any]:
   blocks = []
   for d in vary(1, days+1):
       blocks.append({
           "day": d,
           "morning": f"{metropolis}: espresso + a must-see landmark",
           "afternoon": f"{metropolis}: {vibe} exercise + native lunch",
           "night": f"{metropolis}: sundown spot + dinner + non-obligatory night time stroll"
       })
   return {"device": "draft_itinerary", "days": blocks}
'''