diff --git a/lab-python-error-handling.ipynb b/lab-python-error-handling.ipynb
index f4c6ef6..a68a8e1 100644
--- a/lab-python-error-handling.ipynb
+++ b/lab-python-error-handling.ipynb
@@ -72,11 +72,196 @@
     "\n",
     "4. Test your code by running the program and deliberately entering invalid quantities and product names. Make sure the error handling mechanism works as expected.\n"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "c169f7e4",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Cell 1: products list\n",
+    "products = [\"t-shirt\", \"mug\", \"hat\", \"book\", \"keychain\"]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "6301ba90",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Cell 2: initialize_inventory function\n",
+    "def initialize_inventory(products):\n",
+    "    inventory = {}\n",
+    "\n",
+    "    for product in products:\n",
+    "        valid_input = False\n",
+    "\n",
+    "        while not valid_input:\n",
+    "            try:\n",
+    "                quantity = int(input(f\"Enter the quantity of {product}s available: \"))\n",
+    "\n",
+    "                if quantity >= 0:\n",
+    "                    inventory[product] = quantity\n",
+    "                    valid_input = True\n",
+    "                else:\n",
+    "                    print(\"Quantity cannot be negative. Please enter a valid quantity.\")\n",
+    "\n",
+    "            except ValueError:\n",
+    "                print(\"Invalid input. Please enter a whole number.\")\n",
+    "\n",
+    "    return inventory"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "d87d0756",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Cell 3: get_customer_orders function\n",
+    "def get_customer_orders(inventory):\n",
+    "    customer_orders = {}\n",
+    "\n",
+    "    valid_input = False\n",
+    "\n",
+    "    while not valid_input:\n",
+    "        try:\n",
+    "            number_of_orders = int(input(\"How many different products would the customer like to order? \"))\n",
+    "\n",
+    "            if number_of_orders > 0:\n",
+    "                valid_input = True\n",
+    "            else:\n",
+    "                print(\"Number of orders must be greater than zero.\")\n",
+    "\n",
+    "        except ValueError:\n",
+    "            print(\"Invalid input. Please enter a whole number.\")\n",
+    "\n",
+    "    for i in range(number_of_orders):\n",
+    "        valid_product = False\n",
+    "\n",
+    "        while not valid_product:\n",
+    "            product_order = input(\"Enter the name of a product: \").lower()\n",
+    "\n",
+    "            if product_order not in inventory:\n",
+    "                print(\"Error: That product is not in the inventory.\")\n",
+    "\n",
+    "            elif inventory[product_order] <= 0:\n",
+    "                print(\"Error: That product is out of stock.\")\n",
+    "\n",
+    "            else:\n",
+    "                valid_quantity = False\n",
+    "\n",
+    "                while not valid_quantity:\n",
+    "                    try:\n",
+    "                        order_quantity = int(input(f\"Enter the quantity of {product_order} ordered: \"))\n",
+    "\n",
+    "                        if order_quantity <= 0:\n",
+    "                            print(\"Order quantity must be greater than zero.\")\n",
+    "\n",
+    "                        elif order_quantity > inventory[product_order]:\n",
+    "                            print(f\"Not enough stock. Only {inventory[product_order]} available.\")\n",
+    "\n",
+    "                        else:\n",
+    "                            customer_orders[product_order] = order_quantity\n",
+    "                            valid_quantity = True\n",
+    "                            valid_product = True\n",
+    "\n",
+    "                    except ValueError:\n",
+    "                        print(\"Invalid input. Please enter a whole number.\")\n",
+    "\n",
+    "    return customer_orders"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "id": "324c1f58",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Cell 4: calculate_total_price function\n",
+    "def calculate_total_price(customer_orders):\n",
+    "    total_price = 0.0\n",
+    "\n",
+    "    for product, quantity in customer_orders.items():\n",
+    "        valid_input = False\n",
+    "\n",
+    "        while not valid_input:\n",
+    "            try:\n",
+    "                price = float(input(f\"Enter the price of {product}: \"))\n",
+    "\n",
+    "                if price >= 0:\n",
+    "                    total_price += price * quantity\n",
+    "                    valid_input = True\n",
+    "                else:\n",
+    "                    print(\"Price cannot be negative. Please enter a valid price.\")\n",
+    "\n",
+    "            except ValueError:\n",
+    "                print(\"Invalid input. Please enter a numeric price.\")\n",
+    "\n",
+    "    return total_price"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "id": "ab01adc6",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Cell 5: update_inventory function\n",
+    "def update_inventory(customer_orders, inventory):\n",
+    "    for product, quantity in customer_orders.items():\n",
+    "        inventory[product] -= quantity\n",
+    "\n",
+    "    return inventory"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1f005003",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Error: That product is out of stock.\n",
+      "Error: That product is out of stock.\n",
+      "Error: That product is not in the inventory.\n",
+      "Error: That product is out of stock.\n",
+      "Error: That product is not in the inventory.\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Cell 6: run the program\n",
+    "inventory = initialize_inventory(products)\n",
+    "customer_orders = get_customer_orders(inventory)\n",
+    "total_price = calculate_total_price(customer_orders)\n",
+    "inventory = update_inventory(customer_orders, inventory)\n",
+    "\n",
+    "print(\"Customer orders:\", customer_orders)\n",
+    "print(\"Total price:\", total_price)\n",
+    "print(\"Updated inventory:\", inventory)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "672ea904",
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
+   "display_name": "Python 3",
    "language": "python",
    "name": "python3"
   },
@@ -90,7 +275,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.13"
+   "version": "3.9.10"
   }
  },
  "nbformat": 4,