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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "71293c1d",
+   "metadata": {},
+   "source": [
+    "# Online Banking Assistant\n",
+    "\n",
+    "This application is the Bank of Transformers online banking application.\n",
+    "\n",
+    "Using this application users can:\n",
+    "\n",
+    "- open an account\n",
+    "- add funds to an account\n",
+    "- withdraw funds from an account\n",
+    "- check the balance of accounts\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "989a6bf9",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import os\n",
+    "import json\n",
+    "from dotenv import load_dotenv\n",
+    "from openai import OpenAI\n",
+    "import gradio as gr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "94e7f3d1",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "OpenAI API Key exists and begins sk-proj-\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Initialization\n",
+    "\n",
+    "load_dotenv(override=True)\n",
+    "\n",
+    "openai_api_key = os.getenv('OPENAI_API_KEY')\n",
+    "if openai_api_key:\n",
+    "    print(f\"OpenAI API Key exists and begins {openai_api_key[:8]}\")\n",
+    "else:\n",
+    "    print(\"OpenAI API Key not set\")\n",
+    "    \n",
+    "MODEL = \"gpt-4.1-mini\"\n",
+    "openai = OpenAI()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 64,
+   "id": "d53e4dd8",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "WELCOME = \"\"\"\\\n",
+    "**Welcome to the Bank of Transformers Online Banking App**\n",
+    "\n",
+    "You can do the following:\n",
+    "- open an account\n",
+    "- deposit funds\n",
+    "- withdraw funds\n",
+    "- check the balance of your account\n",
+    "\n",
+    "What would you like to do today?\n",
+    "\"\"\"\n",
+    "\n",
+    "SYS_PROMPT = \"\"\"\\\n",
+    "You are a helpful banking assistant for an online banking app. Your job:\n",
+    "1) Understand the user's intent (open account, deposit, withdraw funds, check balance).\n",
+    "2) If you need to take an action, use the provided tools (functions).\n",
+    "3) Be concise, ask only for the minimum needed info next.\n",
+    "4) Always reflect current balances when relevant.\n",
+    "5) Never invent accounts or balances—rely on tool results only.\n",
+    "6) After carrying out every action for the user, list all available options, as user might want to deposit/withdraw more funds \n",
+    "\"\"\""
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 67,
+   "id": "36d5f7cf",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "open_account_function = {\n",
+    "    \"name\": \"open_account\",\n",
+    "    \"description\": \"Open an account for the user. Ask the user to enter their name and email address.\",\n",
+    "    \"parameters\": {\n",
+    "        \"type\": \"object\",\n",
+    "        \"properties\": {\n",
+    "            \"name\": {\n",
+    "                \"type\": \"string\",\n",
+    "                \"description\": \"The name of the user\",\n",
+    "            },\n",
+    "            \"email\": {\n",
+    "                \"type\": \"string\",\n",
+    "                \"description\": \"The email address of the user\",\n",
+    "            },\n",
+    "        },\n",
+    "        \"required\": [\"name\", \"email\"],\n",
+    "        \"additionalProperties\": False\n",
+    "    }\n",
+    "}\n",
+    "\n",
+    "deposit_funds_function = {\n",
+    "    \"name\": \"deposit_funds\",\n",
+    "    \"description\": \"Deposit funds into the user account. Ask the user to enter the amount to deposit.\",\n",
+    "    \"parameters\": {\n",
+    "        \"type\": \"object\",\n",
+    "        \"properties\": {\n",
+    "            \"amount\": {\n",
+    "                \"type\": \"number\",\n",
+    "                \"description\": \"The amount to deposit\",\n",
+    "            },\n",
+    "            \"balance\": {\n",
+    "                \"type\": \"number\",\n",
+    "                \"description\": \"The account balance before the deposit\",\n",
+    "            }\n",
+    "        },\n",
+    "        \"required\": [\"amount\", \"balance\"],\n",
+    "        \"additionalProperties\": False\n",
+    "    }\n",
+    "}\n",
+    "\n",
+    "withdraw_funds_function = {\n",
+    "    \"name\": \"withdraw_funds\",\n",
+    "    \"description\": \"Withdraw funds from the user account. Ask the user to enter the amount to withdraw.\",\n",
+    "    \"parameters\": {\n",
+    "        \"type\": \"object\",\n",
+    "        \"properties\": {\n",
+    "            \"amount\": {\n",
+    "                \"type\": \"number\",\n",
+    "                \"description\": \"The amount to withdraw\",\n",
+    "            },\n",
+    "            \"balance\": {\n",
+    "                \"type\": \"number\",\n",
+    "                \"description\": \"The account balance before the withdraw\",\n",
+    "            }\n",
+    "        },\n",
+    "        \"required\": [\"amount\", \"balance\"],\n",
+    "        \"additionalProperties\": False\n",
+    "    }\n",
+    "}\n",
+    "\n",
+    "check_balance_function = {\n",
+    "    \"name\": \"check_balance\",\n",
+    "    \"description\": \"Get the balance of the user account and display it to the user.\",\n",
+    "    \"parameters\": {\n",
+    "        \"type\": \"object\",\n",
+    "        \"properties\": {\n",
+    "            \"balance\": {\n",
+    "                \"type\": \"number\",\n",
+    "                \"description\": \"The account balance\",\n",
+    "            }\n",
+    "        },\n",
+    "        \"required\": [\"balance\"],\n",
+    "        \"additionalProperties\": False\n",
+    "    }    \n",
+    "}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 68,
+   "id": "e35f7074",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "tools = [\n",
+    "    {\"type\": \"function\", \"function\": open_account_function}, \n",
+    "    {\"type\": \"function\", \"function\": deposit_funds_function},\n",
+    "    {\"type\": \"function\", \"function\": withdraw_funds_function},\n",
+    "    {\"type\": \"function\", \"function\": check_balance_function}\n",
+    "]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 70,
+   "id": "12cb2f44",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def open_account(name, email):\n",
+    "    return {\"message\": f\"Account opened for {name} with email {email}\"}\n",
+    "\n",
+    "def deposit_funds(amount, balance):\n",
+    "    new_balance = float(balance) + float(amount)\n",
+    "    return {\n",
+    "        \"message\": f\"Deposited ${amount:.2f} into your account. Balance: ${new_balance:.2f}\",\n",
+    "        \"balance\": new_balance\n",
+    "    }\n",
+    "\n",
+    "def withdraw_funds(amount, balance):\n",
+    "    new_balance = float(balance) - float(amount)\n",
+    "    return {\n",
+    "        \"message\": f\"Withdrew ${amount:.2f} from your account. Balance: ${new_balance:.2f}\",\n",
+    "        \"balance\": new_balance\n",
+    "    }\n",
+    "\n",
+    "def check_balance(balance):\n",
+    "    bal = float(balance)\n",
+    "    return {\"message\": f\"Your account balance is: ${bal:.2f}\", \"balance\": bal}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 71,
+   "id": "c05ada4e",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# We have to write that function handle_tool_call:\n",
+    "\n",
+    "def handle_tool_call(assistant_msg, balance):\n",
+    "    tool_messages = []\n",
+    "    new_balance = balance\n",
+    "\n",
+    "    for tc in getattr(assistant_msg, \"tool_calls\", []) or []:\n",
+    "        args = json.loads(tc.function.arguments or \"{}\")\n",
+    "        name = tc.function.name\n",
+    "\n",
+    "        if name == \"open_account\":\n",
+    "            result = open_account(args.get(\"name\"), args.get(\"email\"))\n",
+    "            tool_messages.append({\n",
+    "                \"role\": \"tool\",\n",
+    "                \"tool_call_id\": tc.id,\n",
+    "                \"content\": json.dumps(result)  # MUST be string\n",
+    "            })\n",
+    "\n",
+    "        elif name == \"deposit_funds\":\n",
+    "            result = deposit_funds(args[\"amount\"], new_balance)\n",
+    "            new_balance = result[\"balance\"]\n",
+    "            tool_messages.append({\n",
+    "                \"role\": \"tool\",\n",
+    "                \"tool_call_id\": tc.id,\n",
+    "                \"content\": json.dumps(result)\n",
+    "            })\n",
+    "\n",
+    "        elif name == \"withdraw_funds\":\n",
+    "            result = withdraw_funds(args[\"amount\"], new_balance)\n",
+    "            new_balance = result[\"balance\"]\n",
+    "            tool_messages.append({\n",
+    "                \"role\": \"tool\",\n",
+    "                \"tool_call_id\": tc.id,\n",
+    "                \"content\": json.dumps(result)\n",
+    "            })\n",
+    "\n",
+    "        elif name == \"check_balance\":\n",
+    "            result = check_balance(new_balance)\n",
+    "            tool_messages.append({\n",
+    "                \"role\": \"tool\",\n",
+    "                \"tool_call_id\": tc.id,\n",
+    "                \"content\": json.dumps(result)\n",
+    "            })\n",
+    "\n",
+    "    return tool_messages, new_balance\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 72,
+   "id": "7200d772",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "* Running on local URL:  http://127.0.0.1:7879\n",
+      "* To create a public link, set `share=True` in `launch()`.\n"
+     ]
+    },
+    {
+     "data": {
+      "text/html": [
+       "<div><iframe src=\"http://127.0.0.1:7879/\" width=\"100%\" height=\"500\" allow=\"autoplay; camera; microphone; clipboard-read; clipboard-write;\" frameborder=\"0\" allowfullscreen></iframe></div>"
+      ],
+      "text/plain": [
+       "<IPython.core.display.HTML object>"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    },
+    {
+     "data": {
+      "text/plain": []
+     },
+     "execution_count": 72,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "def chat(message, history, balance):\n",
+    "    # Build messages from history (which already includes the welcome assistant turn)\n",
+    "    messages = [{\"role\": \"system\", \"content\": SYS_PROMPT}] + history + [\n",
+    "        {\"role\": \"user\", \"content\": message}\n",
+    "    ]\n",
+    "\n",
+    "    resp = openai.chat.completions.create(model=MODEL, messages=messages, tools=tools)\n",
+    "    assistant_msg = resp.choices[0].message\n",
+    "\n",
+    "    # If the model called tools\n",
+    "    if getattr(assistant_msg, \"tool_calls\", None):\n",
+    "        # 1) Append the assistant's tool-call turn as a normal message dict\n",
+    "        messages.append({\n",
+    "            \"role\": \"assistant\",\n",
+    "            \"content\": assistant_msg.content or \"\",\n",
+    "            \"tool_calls\": [\n",
+    "                {\n",
+    "                    \"id\": tc.id,\n",
+    "                    \"type\": \"function\",\n",
+    "                    \"function\": {\n",
+    "                        \"name\": tc.function.name,\n",
+    "                        \"arguments\": tc.function.arguments,\n",
+    "                    },\n",
+    "                } for tc in assistant_msg.tool_calls\n",
+    "            ],\n",
+    "        })\n",
+    "\n",
+    "        # 2) Execute tools and extend with tool messages\n",
+    "        tool_msgs, balance = handle_tool_call(assistant_msg, balance)\n",
+    "        messages.extend(tool_msgs)  # NOT append\n",
+    "\n",
+    "        # 3) Ask the model to finalize using tool results\n",
+    "        resp2 = openai.chat.completions.create(model=MODEL, messages=messages, tools=tools)\n",
+    "        return resp2.choices[0].message.content, balance\n",
+    "\n",
+    "    # No tools—just return the assistant text\n",
+    "    return assistant_msg.content, balance\n",
+    "\n",
+    "# Pre-seed the Chatbot with the welcome as the first assistant message\n",
+    "chatbot = gr.Chatbot(\n",
+    "    value=[{\"role\": \"assistant\", \"content\": WELCOME}],\n",
+    "    type=\"messages\",\n",
+    "    height=420\n",
+    ")\n",
+    "\n",
+    "balance_state = gr.State(0.0)\n",
+    "\n",
+    "gr.ChatInterface(\n",
+    "    fn=chat,\n",
+    "    chatbot=chatbot,   # <-- inject our pre-seeded Chatbot\n",
+    "    type=\"messages\",\n",
+    "    additional_inputs=[balance_state],   # read current balance\n",
+    "    additional_outputs=[balance_state],  # write updated balance\n",
+    ").launch()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "98256294",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": ".venv",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.12.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}