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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "turkish-shopper",
+   "metadata": {},
+   "source": [
+    "## Question 1:\n",
+    "Create the class `Society` with following information:\n",
+    "\n",
+    "`society_name`, `house_no`, `no_of_members`, `flat`, `income`\n",
+    "\n",
+    "**Methods :**\n",
+    "\n",
+    "*\t An `__init__` method to assign initial values of `society_name`, `flat`, `house_no`, `no_of_members`, `income`\n",
+    "*\t`input_data()` To read information from members\n",
+    "*\t`allocate_flat()` To allocate flat according to income using the below table.\n",
+    "*\t`show_data()` to display the details of the entire class.\n",
+    "\n",
+    "![image](https://user-images.githubusercontent.com/48380735/107130781-429d7100-68d1-11eb-90df-246107a2677b.png)\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 45,
+   "id": "adapted-future",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class Society(object):\n",
+    "    \n",
+    "    def allocate_flat(self):\n",
+    "        if self.income>=25000:\n",
+    "            self.flat='A Type'\n",
+    "        elif self.income>=20000:\n",
+    "            self.flat='B Type'\n",
+    "        elif self.income>=15000:\n",
+    "            self.flat='C Type'\n",
+    "        else:\n",
+    "            self.flat='D Type'\n",
+    "        \n",
+    "    def __init__ (self,society_name, house_no ,no_of_members,income,flat=None):\n",
+    "        self.society_name=society_name\n",
+    "        self.house_no=house_no\n",
+    "        self.no_of_members=no_of_members\n",
+    "        self.income=income\n",
+    "        self.allocate_flat()\n",
+    "\n",
+    "    def input_data(self):\n",
+    "        self.society_name=input(\"Please enter the society name: \")\n",
+    "        self.house_no=int(input(\"Please enter the house no: \"))\n",
+    "        self.no_of_members=int(input(\"Please enter the number of members: \"))\n",
+    "        self.income=int(input(\"Please enter the income: \"))\n",
+    "        self.allocate_flat()\n",
+    "        \n",
+    "    def show_data(self):\n",
+    "        print(f\"\"\"Society Name\\t:\\t{self.society_name}\n",
+    "House Number\\t:\\t{self.house_no}\n",
+    "No of Members\\t:\\t{self.no_of_members}\n",
+    "Flat\\t\\t:\\t{self.flat}\n",
+    "Income\\t\\t:\\t{self.income}\"\"\")\n",
+    "   "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 46,
+   "id": "atlantic-might",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Society Name\t:\tMilkyway Apartment\n",
+      "House Number\t:\t8\n",
+      "No of Members\t:\t14\n",
+      "Flat\t\t:\tA Type\n",
+      "Income\t\t:\t26000\n"
+     ]
+    }
+   ],
+   "source": [
+    "society_1=Society('Milkyway Apartment',8,14,26000)\n",
+    "society_2=Society('Fullmoon Apartment',15,11,21000)\n",
+    "society_3=Society('Venus Apartment',10,7,14000)\n",
+    "\n",
+    "society_1.show_data()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 47,
+   "id": "revolutionary-server",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Please enter the society name: Kilyos Apartment\n",
+      "Please enter the house no: 7\n",
+      "Please enter the number of members: 12\n",
+      "Please enter the income: 10000\n"
+     ]
+    }
+   ],
+   "source": [
+    "society_1.input_data()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 48,
+   "id": "careful-pencil",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Society Name\t:\tKilyos Apartment\n",
+      "House Number\t:\t7\n",
+      "No of Members\t:\t12\n",
+      "Flat\t\t:\tD Type\n",
+      "Income\t\t:\t10000\n"
+     ]
+    }
+   ],
+   "source": [
+    "society_1.show_data()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "dress-composer",
+   "metadata": {},
+   "source": [
+    "## Question 2:\n",
+    "Define a class named `ItemInfo` with the following description:\n",
+    "\n",
+    "`item_code`(Item Code), `item`(item name), `price`(Price of each item), `qty`(quantity in stock), `discount`(Discount percentage on the item), `net_price`(Price after discount)\n",
+    "\n",
+    "**Methods :**\n",
+    "*\tA member method `calculate_discount()` to calculate discount as per the following rules:\n",
+    "*\tIf `qty <= 10` —> discount is `0`\n",
+    "*\tIf `qty (11 to 20 inclusive)` —> discount is `15`\n",
+    "*\tIf `qty >= 20` —> discount is `20`\n",
+    "*\tA constructor init method to assign the initial values for `item_code` to `0` and `price`, `qty`, `net_price` and `discount` to `null`\n",
+    "*\tA function called `buy()` to allow user to enter values for `item_code`, `item`, `price`, `qty`. Then call function `calculate_discount()` to calculate the `discount` and `net_price`(price * qty - discount).\n",
+    "*\tA function `show_all()` or similar name to allow user to view the content of all the data members.\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "id": "fourth-exhaust",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class ItemInfo(object):\n",
+    "    \n",
+    "    def calculate_discount(self):\n",
+    "        if self.qty <= 10:\n",
+    "            self.discount = 0\n",
+    "        elif self.qty <= 20:\n",
+    "            self.discount = 15\n",
+    "        else:\n",
+    "            self.discount = 20\n",
+    "        self.net_price = round(self.price * self.qty * (1-self.discount/100),1)\n",
+    "         \n",
+    "        \n",
+    "    def __init__(self, item_code=0, item=None, price=None, qty=None, discount=None, net_price=None):\n",
+    "        self.item_code = item_code\n",
+    "        self.item = item\n",
+    "        self.price = price\n",
+    "        self.qty = qty\n",
+    "        self.calculate_discount()\n",
+    "        \n",
+    "    def buy(self):\n",
+    "        self.item_code=int(input(\"Please enter the item code: \"))\n",
+    "        self.item=input(\"Please enter the item name: \")\n",
+    "        self.price=int(input(\"Please enter the price of item \"))\n",
+    "        self.qty=int(input(\"Please enter the quantity in stock: \"))\n",
+    "        self.calculate_discount()\n",
+    "        \n",
+    "    def show_all(self):\n",
+    "        print(f\"\"\"Item Code\\t:\\t{self.item_code}\n",
+    "Item Name\\t:\\t{self.item}\n",
+    "Price\\t\\t:\\t€{self.price}\n",
+    "Quantity\\t:\\t{self.qty}\n",
+    "Discount\\t:\\t%{self.discount}\n",
+    "Net Price\\t:\\t{self.net_price}\"\"\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 22,
+   "id": "broadband-brook",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Item Code\t:\t12478\n",
+      "Item Name\t:\tbutter\n",
+      "Price\t\t:\t€6\n",
+      "Quantity\t:\t12\n",
+      "Discount\t:\t%15\n",
+      "Net Price\t:\t61.2\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_1 = ItemInfo(12345,'icecream', 4, 10)\n",
+    "product_2 = ItemInfo(12478,'butter', 6, 12)\n",
+    "product_3 = ItemInfo(96325,'yogurt', 3, 5)\n",
+    "\n",
+    "product_2.show_all()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 23,
+   "id": "remarkable-newark",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Please enter the item code: 96325\n",
+      "Please enter the item name: yogurt\n",
+      "Please enter the price of item 10\n",
+      "Please enter the quantity in stock: 3\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_3.buy()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 24,
+   "id": "terminal-campbell",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Item Code\t:\t96325\n",
+      "Item Name\t:\tyogurt\n",
+      "Price\t\t:\t€10\n",
+      "Quantity\t:\t3\n",
+      "Discount\t:\t%0\n",
+      "Net Price\t:\t30.0\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_3.show_all()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "latin-delight",
+   "metadata": {},
+   "source": [
+    "## Question 3:\n",
+    "\n",
+    "Define a class named `Product` with the following specifications:\n",
+    "#### Data members:\n",
+    "* `product_id` – A string to store product.\n",
+    "* `product_name` - A string to store the name of the product. \n",
+    "* `product_purchase_price` – A flo to store the cost price of the product.\n",
+    "* `product_sale_price` – A decimal to store Sale Price \n",
+    "* `Margin` - A decimal to be calculated as `(product_sale_price - product_purchase_price)`\n",
+    "\n",
+    "**Remarks** - To store \"Profit\" if Margin is positive else \"Loss\" if Margin is negative.\n",
+    "\n",
+    "**Methods :**\n",
+    "*\tA constructor to intialize all the data members with valid default values.\n",
+    "*\tA method `set_remarks()` that assigns Margin as `(product_sale_price - product_purchase_price)` and sets Remarks as mentioned below :\n",
+    "\n",
+    "![image](https://user-images.githubusercontent.com/48380735/107130956-d91e6200-68d2-11eb-92e3-74006ce1127c.png)\n",
+    "\n",
+    "*\tA method `set_details()` to accept values for `product_id`. `product_name`, `product_purchase_price`, `product_sale_price` and invokes `SetRemarks()` method.\n",
+    "*\tA method `get_details()` that displays all the data members.\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 41,
+   "id": "unexpected-identifier",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class Product(object):\n",
+    "    \n",
+    "    def set_remarks(self):\n",
+    "        self.margin = round(self.product_sale_price - self.product_purchase_price,1)\n",
+    "        self.remark = 'Loss' if self.margin < 0 else 'Profit'\n",
+    "         \n",
+    "        \n",
+    "    def __init__(self, product_id=None, product_name=None, product_purchase_price=None, product_sale_price=None, margin=None):\n",
+    "        self.product_id = product_id\n",
+    "        self.product_name = product_name\n",
+    "        self.product_purchase_price = product_purchase_price\n",
+    "        self.product_sale_price = product_sale_price\n",
+    "        self.set_remarks()\n",
+    "        \n",
+    "\n",
+    "    def set_details(self):\n",
+    "        self.product_id=input(\"Please enter the product id: \")\n",
+    "        self.product_name=input(\"Please enter the product name: \")\n",
+    "        self.product_purchase_price=float(input(\"Please enter the product purchase price \"))\n",
+    "        self.product_sale_price=float(input(\"Please enter the product sale price: \"))\n",
+    "        self.set_remarks()\n",
+    "        \n",
+    "    def get_details(self):\n",
+    "        print(f\"\"\"Product Id\\t\\t:\\t{self.product_id}\n",
+    "Product Name\\t\\t:\\t{self.product_name}\n",
+    "Product Purchase Price\\t:\\t€{self.product_purchase_price}\n",
+    "Product Sale Price\\t:\\t€{self.product_sale_price}\n",
+    "Margin\\t\\t\\t:\\t€{self.margin}\n",
+    "Remark\\t\\t\\t:\\t{self.remark}\"\"\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "id": "virgin-jackson",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Product Id\t\t:\tE12478\n",
+      "Product Name\t\t:\tbutter\n",
+      "Product Purchase Price\t:\t€6.5\n",
+      "Product Sale Price\t:\t€8.1\n",
+      "Margin\t\t\t:\t€1.6\n",
+      "Remark\t\t\t:\tProfit\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_1 = Product('A12345','icecream', 4.3, 7.2)\n",
+    "product_2 = Product('E12478','butter', 6.5, 8.1)\n",
+    "product_3 = Product('C96325','yogurt', 5.6, 7.5)\n",
+    "\n",
+    "product_2.get_details()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 43,
+   "id": "competent-tolerance",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Please enter the product id: Z12345\n",
+      "Please enter the product name: bread\n",
+      "Please enter the product purchase price 1\n",
+      "Please enter the product sale price: 1.5\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_1.set_details()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 44,
+   "id": "successful-cotton",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Product Id\t\t:\tZ12345\n",
+      "Product Name\t\t:\tbread\n",
+      "Product Purchase Price\t:\t€1.0\n",
+      "Product Sale Price\t:\t€1.5\n",
+      "Margin\t\t\t:\t€0.5\n",
+      "Remark\t\t\t:\tProfit\n"
+     ]
+    }
+   ],
+   "source": [
+    "product_1.get_details()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "clinical-responsibility",
+   "metadata": {},
+   "source": [
+    "## Question 4:\n",
+    "Write a `Customer` class and `Items` class. \n",
+    "Let user enter customer information and add stuff to his/her shopping card.\n",
+    "\n",
+    "### Class `Items` :\n",
+    "**Method :**\n",
+    "`__init__()`, `__str__()`, `calculate_discount()`, `shopping_cart()`, `get_total_amount()`\n",
+    "\n",
+    "**calculate_discount()**\n",
+    "*\t`total_price` = `price` * `qty`\n",
+    "*\tdiscount —> `25%` if `total_price >= 4000`\n",
+    "*\tdiscount —> `15%` if `total_price >= 2000`\n",
+    "*\tdiscount —> `10%` if `total_price < 2000`\n",
+    "*\t`price_tobe_paid` = `total_price – discount`\n",
+    "\n",
+    "**shopping_cart()**\n",
+    "* Let user add items in the shopping basket. Be creative with the items, set their prices as well. \n",
+    "\n",
+    "**_\\_str\\_\\_()**\n",
+    "*\tPrint items added and total price nicely.\n",
+    "\n",
+    "### Class `Customer` :\n",
+    "**Methods:** \n",
+    "`__init__()`, `get_cust_info()` this is optional, `__str__()`\n",
+    "\n",
+    "Optionally create a `get_cust_info()` or similar to allow customer to enter his/her information or just define them in `__init__()` and pass customer information as arguments while creating a customer object.\n",
+    "\n",
+    "**_\\_str\\_\\_()**\n",
+    "\n",
+    "*\tPrint customer information and price nicely.\n",
+    "\n",
+    "Find a way to link two classes. For example, instances of both classes may have a customer number. With a get method, get the customer number and pass it to the item object as an argument to set customer number attribute. \n",
+    "So `Customer` class instance holds the customer info, `Items` class holds the shopped item’s info for the same customer ID number such as price, quantity or so. \n",
+    "\n",
+    "In the end, print both info (customer info and shopped items info) using their respective `__str__` format in a nice way. \n",
+    "\n",
+    "**Simple example:**\n",
+    "\n",
+    "`Customer1 = [name : Jack, last_name : Russel, customer_id : 123]`\n",
+    "\n",
+    "`shopping_cart1 = [customer_id : 123, items : [necklace, ring, ear ring], total_price : 2000, discount : 300,  price_tobe_paid : 1700]`\n",
+    "\n",
+    "Crate a few customers and print their information (Personal and shopping info). \n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "dominican-watershed",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class Customer(object):\n",
+    "    customer_ids, names, last_names = [], [], []\n",
+    "\n",
+    "    def __init__(self, customer_id=None, name=None, last_name=None):\n",
+    "        self.customer_id = customer_id\n",
+    "        self.name = name\n",
+    "        self.last_name = last_name\n",
+    "        if self.customer_id is not None:\n",
+    "            Customer.customer_ids.append(self.customer_id)\n",
+    "            Customer.names.append(self.name)\n",
+    "            Customer.last_names.append(self.last_name)\n",
+    "                \n",
+    "    @property\n",
+    "    def get_full_name(self):\n",
+    "        return \"{} {}\".format(self.name,self.last_name)\n",
+    "    \n",
+    "    def __str__(self):\n",
+    "        return f\"\"\"Customer id\\t: {self.customer_id}\n",
+    "Full Name\\t: {self.name} {self.last_name}\"\"\"\n",
+    "      \n",
+    "    def set_cust_info(self):\n",
+    "        self.customer_id = int(input(\"Please enter your customer id: \"))\n",
+    "        self.name = input(\"Please enter your first name: \")\n",
+    "        self.last_name = input(\"Please enter your last name: \")\n",
+    "        if self.customer_id is not None:\n",
+    "            Customer.customer_ids.append(self.customer_id)\n",
+    "            Customer.names.append(self.name)\n",
+    "            Customer.last_names.append(self.last_name)\n",
+    "\n",
+    "    @classmethod\n",
+    "    def get_cust_info(cls):\n",
+    "        print(\"\\nAll Customer Informations:\\n--------------------------\")\n",
+    "        for i in range(len(Customer.customer_ids)):\n",
+    "            print(f\"\"\"Customer Id\\t: {Customer.customer_ids[i]}     \n",
+    "Full Name\\t: {Customer.names[i]} {Customer.last_names[i]}\\n\"\"\")\n",
+    "\n",
+    "\n",
+    "class Items(Customer):\n",
+    "    \n",
+    "    customer_ids, items, quantities, unit_prices = [],[],[],[]\n",
+    "    total_prices, discounts, price_tobe_paids = [],[],[]\n",
+    "    \n",
+    "    def get_total_amount(self): \n",
+    "        self.total_price = self.quantity * self.unit_price\n",
+    "        return self.total_price\n",
+    "    \n",
+    "    def calculate_discount(self):  \n",
+    "        self.total_price = self.get_total_amount()\n",
+    "        \n",
+    "        if self.total_price >= 4000:\n",
+    "            self.discount = 25\n",
+    "        elif self.total_price >= 2000:\n",
+    "            self.discount = 15\n",
+    "        else:\n",
+    "            self.discount = 10\n",
+    "            \n",
+    "        self.price_tobe_paid = round(self.total_price * (1-self.discount/100),1)\n",
+    "        \n",
+    "        if self.customer_id is not None:\n",
+    "            Items.total_prices.append(self.total_price)\n",
+    "            Items.discounts.append(self.discount)\n",
+    "            Items.price_tobe_paids.append(self.price_tobe_paid)\n",
+    "\n",
+    "    def __init__(self, customer_id=None, item=None, quantity=None, unit_price=None):\n",
+    "        self.customer_id = customer_id\n",
+    "        self.item = item\n",
+    "        self.quantity = quantity\n",
+    "        self.unit_price = unit_price\n",
+    "        \n",
+    "        if self.customer_id is not None:\n",
+    "            Items.customer_ids.append(self.customer_id)\n",
+    "            Items.items.append(self.item)\n",
+    "            Items.quantities.append(self.quantity)\n",
+    "            Items.unit_prices.append(self.unit_price)\n",
+    "            self.calculate_discount()\n",
+    "    \n",
+    "    def __str__(self):\n",
+    "        return f\"\"\"Customer id\\t: {self.customer_id}\n",
+    "Item\\t\\t: {self.item}\n",
+    "Unit Price\\t: €{self.unit_price}\n",
+    "Quantity\\t: {self.quantity}\n",
+    "Total price\\t: €{self.total_price}\n",
+    "Discount\\t: %{self.discount}\n",
+    "Net Amount Paid\\t: €{self.price_tobe_paid}\"\"\"\n",
+    "         \n",
+    "    def shopping_cart(self):\n",
+    "        self.customer_id = int(input(\"Please enter the customer id: \"))\n",
+    "        self.item = input(\"Please enter the item: \")\n",
+    "        self.quantity = int(input(f\"Please enter the quantity of item: \"))\n",
+    "        self.unit_price = int(input(f\"please enter the unit price of item: \")) \n",
+    "        \n",
+    "        if self.customer_id is not None:\n",
+    "            Items.customer_ids.append(self.customer_id)\n",
+    "            Items.items.append(self.item)\n",
+    "            Items.quantities.append(self.quantity)\n",
+    "            Items.unit_prices.append(self.unit_price)\n",
+    "            self.calculate_discount()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "functional-frequency",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def merge(ob1, ob2):\n",
+    "    ob1.__dict__.update(ob2.__dict__)\n",
+    "    return ob1\n",
+    "\n",
+    "def get_all():\n",
+    "    for i in range(len(Customer.customer_ids)):\n",
+    "        print(f'\\n{i+1}. Customer:\\n-----------------')\n",
+    "        inst = eval(f\"merge( item_{i+1}, customer_{i+1} )\")\n",
+    "        print(f\"\"\"Customer Id\\t: {inst.customer_id}\n",
+    "Full Name\\t: {inst.name} {inst.last_name}\n",
+    "Item\\t\\t: {inst.item}\n",
+    "Quantity\\t: {inst.quantity}\n",
+    "Unit Price\\t: {inst.unit_price}\n",
+    "Total Price\\t: €{inst.total_price}\n",
+    "Discount\\t: %{inst.discount}\n",
+    "Price Tobe Paid\\t: €{inst.price_tobe_paid}\"\"\") "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "amino-regression",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Define item objects\n",
+    "item_1=Items(11111,'dinner set',1,3500)\n",
+    "item_2=Items(22222,'necklace',3,2000)\n",
+    "item_3=Items(33333,'ring',2,1500)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "id": "another-activity",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Define customer objects\n",
+    "customer_1=Customer(11111,'Fatih','Fidan')\n",
+    "customer_2=Customer(22222,'Ahmet','Altan')\n",
+    "customer_3=Customer(33333,'Atilla','Tas')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "id": "martial-campaign",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Fatih Fidan\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Display the full name of any customer\n",
+    "print(customer_1.get_full_name)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "id": "duplicate-coordinator",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Customer id\t: 33333\n",
+      "Full Name\t: Atilla Tas\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Display the info of any customer \n",
+    "print(str(customer_3))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "id": "absent-terrace",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\n",
+      "All Customer Informations:\n",
+      "--------------------------\n",
+      "Customer Id\t: 11111     \n",
+      "Full Name\t: Fatih Fidan\n",
+      "\n",
+      "Customer Id\t: 22222     \n",
+      "Full Name\t: Ahmet Altan\n",
+      "\n",
+      "Customer Id\t: 33333     \n",
+      "Full Name\t: Atilla Tas\n",
+      "\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Display the infos of all customers\n",
+    "Customer.get_cust_info()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "id": "unlimited-tamil",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Please enter your customer id: 44444\n",
+      "Please enter your first name: Bill\n",
+      "Please enter your last name: Gates\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Define a new customer, enter the infos from keyboard\n",
+    "customer_4 = Customer()\n",
+    "customer_4.set_cust_info()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "id": "divine-coffee",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Customer id\t: 44444\n",
+      "Full Name\t: Bill Gates\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Display the infos of the last customer \n",
+    "print(str(customer_4))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "id": "coated-matrix",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Please enter the customer id: 44444\n",
+      "Please enter the item: car\n",
+      "Please enter the quantity of item: 1\n",
+      "please enter the unit price of item: 5000\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Define a new item, enter the infos from keyboard\n",
+    "# Be careful, Its customer_id must be same with the corresponding object in Customer class.\n",
+    "item_4 = Items()\n",
+    "item_4.shopping_cart()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "id": "studied-estate",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Customer id\t: 44444\n",
+      "Item\t\t: car\n",
+      "Unit Price\t: €5000\n",
+      "Quantity\t: 1\n",
+      "Total price\t: €5000\n",
+      "Discount\t: %25\n",
+      "Net Amount Paid\t: €3750.0\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Display the infos of the last item.\n",
+    "print(str(item_4))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "id": "beneficial-impossible",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\n",
+      "1. Customer:\n",
+      "-----------------\n",
+      "Customer Id\t: 11111\n",
+      "Full Name\t: Fatih Fidan\n",
+      "Item\t\t: dinner set\n",
+      "Quantity\t: 1\n",
+      "Unit Price\t: 3500\n",
+      "Total Price\t: €3500\n",
+      "Discount\t: %15\n",
+      "Price Tobe Paid\t: €2975.0\n",
+      "\n",
+      "2. Customer:\n",
+      "-----------------\n",
+      "Customer Id\t: 22222\n",
+      "Full Name\t: Ahmet Altan\n",
+      "Item\t\t: necklace\n",
+      "Quantity\t: 3\n",
+      "Unit Price\t: 2000\n",
+      "Total Price\t: €6000\n",
+      "Discount\t: %25\n",
+      "Price Tobe Paid\t: €4500.0\n",
+      "\n",
+      "3. Customer:\n",
+      "-----------------\n",
+      "Customer Id\t: 33333\n",
+      "Full Name\t: Atilla Tas\n",
+      "Item\t\t: ring\n",
+      "Quantity\t: 2\n",
+      "Unit Price\t: 1500\n",
+      "Total Price\t: €3000\n",
+      "Discount\t: %15\n",
+      "Price Tobe Paid\t: €2550.0\n",
+      "\n",
+      "4. Customer:\n",
+      "-----------------\n",
+      "Customer Id\t: 44444\n",
+      "Full Name\t: Bill Gates\n",
+      "Item\t\t: car\n",
+      "Quantity\t: 1\n",
+      "Unit Price\t: 5000\n",
+      "Total Price\t: €5000\n",
+      "Discount\t: %25\n",
+      "Price Tobe Paid\t: €3750.0\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Merge and display all infos came from Customer and Items Classes.\n",
+    "get_all()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "turkish-furniture",
+   "metadata": {},
+   "source": [
+    "## Question 5 (Optional):\n",
+    "\n",
+    "Could be a long term project as you may have time.\n",
+    "Create a simple game like TicTacToe or similar (Black Jack, paper-scissor-rock etc.) using Object Oriented Programming methodology.\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "fitted-omaha",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "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": "3.8.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}