class_13_20200112_OOP2.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Object Oriented Programming Concepts (Continued)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Topics:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- Encapsulation\n",
    "- Abstraction\n",
    "- Exception Handling\n",
    "- File Handling\n",
    "- Package\n",
    "- Model"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Encapsulation:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- Encapsulation can be used to hide data members and member functions. Under this definition, encapsulation means that the internal representation of an object is generally hidden from view outside of the object's definition. Typically, only the object's own methods can directly inspect or manipulate its fields.\n",
    "  1. Creating Class\n",
    "  2. Making some methods / attributes private\n",
    "  3. Making a function (getter / setter ) to change those private methods / attributes."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Abstraction:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- Abstraction means displaying only essential information and hiding the details\n",
    "- Abstraction means displaying only essential information and hiding the details. Data abstraction refers to providing only essential information about the data to the outside world, hiding the background details or implementation. Consider a real life example of a man driving a car. ... This is what abstraction is.\n",
    "- Abstract classes are classes that contain one or more abstract methods. An abstract method is a method that is declared, but contains no implementation. Abstract classes may not be instantiated, and require subclasses to provide implementations for the abstract methods."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Exception Handling:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- Handling errors while executing program is called \"Exception Handling\""
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "##  Package & Module:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- A container of files like a folder is considered as a \"Package\"\n",
    "- Files in the package are called \"Module\""
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Practice:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Encapsulation:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "class A():\n",
    "    def __init__(self, name, age):\n",
    "        self.__sName = name       # double 'underscore' is used to make an indentifier 'private'\n",
    "        self.__sAge = age\n",
    "    \n",
    "    def display(self):\n",
    "        print(\"Name: \", self.__sName)\n",
    "        print(\"Age: \", self.__sAge)\n",
    "    \n",
    "    def change(self, a, b):    # a, b are local variables\n",
    "        self.__sName = a\n",
    "        self.__sAge = b\n",
    "        \n",
    "    def __info(self):\n",
    "        print(\"Hello World\")\n",
    "        \n",
    "    def abc(self):\n",
    "        self.__info()\n",
    "    \n",
    "obj1 = A('Ali', 25)    # it will generate error being 'sName' as a private identifier"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "ename": "AttributeError",
     "evalue": "'A' object has no attribute 'sName'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-2-5f759b51926c>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;31m# sName is a private variable name, therefore, will not execute rather will generate error\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 2\u001b[1;33m \u001b[0mobj1\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0msName\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m: 'A' object has no attribute 'sName'"
     ]
    }
   ],
   "source": [
    "# sName is a private variable name, therefore, will not execute rather will generate error\n",
    "obj1.sName"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "ename": "AttributeError",
     "evalue": "'A' object has no attribute '__sName'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-2-3f8afe5f35ed>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;31m# using double underscore will also not access private identifier\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m \u001b[0mobj1\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m__sName\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m: 'A' object has no attribute '__sName'"
     ]
    }
   ],
   "source": [
    "# using double underscore will also not access private identifier\n",
    "\n",
    "obj1.__sName"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Ali'"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# accessing private identifier using class reference\n",
    "\n",
    "obj1._A__sName"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Name:  Ali\n",
      "Age:  25\n"
     ]
    }
   ],
   "source": [
    "# accessing private identifier / variable name using a 'method' named 'display'\n",
    "\n",
    "obj1.display()   # this is an example of \"getter\" function"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Name:  Ismail\n",
      "Age:  28\n"
     ]
    }
   ],
   "source": [
    "obj1.change(\"Ismail\", 28)    # this is an example of \"setter\" function\n",
    "\n",
    "obj1.display()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello World\n"
     ]
    }
   ],
   "source": [
    "# accessing info, a private method using a public function 'abc'\n",
    "\n",
    "obj1.abc()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Abstract Class:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "class A:     # abstract class\n",
    "    def __init__(self, a, b):\n",
    "        self.a = a\n",
    "        self.b = b\n",
    "\n",
    "class B(A):\n",
    "    pass"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [],
   "source": [
    "obj1 = A(2,5)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n",
      "5\n"
     ]
    }
   ],
   "source": [
    "print(obj1.a)\n",
    "print(obj1.b)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "obj2 = B(7,9)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "Can't instantiate abstract class A with abstract methods __init__, abc",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-11-543d7f2cb9dd>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m     16\u001b[0m     \u001b[1;32mpass\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     17\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 18\u001b[1;33m \u001b[0mobj1\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mA\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m5\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m7\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: Can't instantiate abstract class A with abstract methods __init__, abc"
     ]
    }
   ],
   "source": [
    "from abc import  ABC, abstractmethod        # abc.py is a built-in module which is imported here\n",
    "                                            # ABC is a class & 'abstractmethod' is a function\n",
    "\n",
    "class A(ABC):\n",
    "    \n",
    "    @abstractmethod\n",
    "    def __init__(self, a, b):\n",
    "        self.a = a\n",
    "        self.b = b\n",
    "        \n",
    "    @abstractmethod     # to convert construction as an 'abstract' method\n",
    "    def abc():\n",
    "        pass\n",
    "\n",
    "class B(A):\n",
    "    pass\n",
    "\n",
    "obj1 = A(5,7)  # instnace will not be initated being abstract class"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "Can't instantiate abstract class B with abstract methods __init__, abc",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-12-8ff2c6b483fe>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mobj2\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mB\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m5\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m7\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: Can't instantiate abstract class B with abstract methods __init__, abc"
     ]
    }
   ],
   "source": [
    "obj2 = B(5,7)   # instance will not instantiated"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "Can't instantiate abstract class Human with abstract methods __init__",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-31-675ff69fbe07>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m     18\u001b[0m         \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mage\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mb\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     19\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 20\u001b[1;33m \u001b[0mp1\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mHuman\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m     21\u001b[0m \u001b[0mp1\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mdisplay\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m'Qasim'\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m25\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mTypeError\u001b[0m: Can't instantiate abstract class Human with abstract methods __init__"
     ]
    }
   ],
   "source": [
    "from abc import ABC, abstractmethod\n",
    "\n",
    "class Human(ABC):    # making 'human' class, a child of 'ABC' parent class\n",
    "    \n",
    "    \n",
    "    @abstractmethod\n",
    "    def __init__(self):\n",
    "        self.name = None\n",
    "        self.age = None\n",
    "        \n",
    "    def display(self, name, age):\n",
    "        self.name = name\n",
    "        self.age = age\n",
    "        return \"Object name is {} and he is {} years old\".format(self.name, self.age)\n",
    "    \n",
    "    def change(self, a, b):    # a, b are local variables\n",
    "        self.name = a\n",
    "        self.age = b\n",
    "\n",
    "p1 = Human()\n",
    "p1.display('Qasim',25)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {},
   "outputs": [],
   "source": [
    "class Male(Human):\n",
    "    \n",
    "    def __init__(self):\n",
    "        self.name = 'Qasim'\n",
    "        self.fName = 'Aslam'\n",
    "        \n",
    "    def laughter(self):\n",
    "        return 'Hahahahahaha'\n",
    "    \n",
    "p1=Male()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Hahahahahaha'"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "p1.laughter()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Aslam'"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "p1.fName"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Object name is Muhammad Ismail and he is 28 years old'"
      ]
     },
     "execution_count": 33,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "p1.display(\"Muhammad Ismail\", 28)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Task-1:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Create a 'Parent' class\n",
    "\n",
    "class A():\n",
    "    def __init__(self):\n",
    "        self.name = \"\"    # attribute\n",
    "        self.fname = \"\"   # attribute\n",
    "    \n",
    "    def speak(self, words=\"\"):    # method\n",
    "        print(words, \"....\")\n",
    "    \n",
    "    def eat(self, food=\"Bread\"):   # method\n",
    "        print(food)\n",
    "\n",
    "#  Create a 'Child' calss\n",
    "class B(A):\n",
    "    pass"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Zafar Abbas\n"
     ]
    }
   ],
   "source": [
    "c_obj1 = B()\n",
    "c_obj1.name = \"Zafar Abbas\"\n",
    "print(c_obj1.name)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Exception Handling:"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Zero Division Error:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Pakistan\n",
      "Pakistan\n"
     ]
    },
    {
     "ename": "ZeroDivisionError",
     "evalue": "division by zero",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mZeroDivisionError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-14-5a6a6e4946c7>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Pakistan\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Pakistan\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m7\u001b[0m \u001b[1;33m/\u001b[0m \u001b[1;36m0\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      4\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Pakistan\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      5\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Pakistan\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mZeroDivisionError\u001b[0m: division by zero"
     ]
    }
   ],
   "source": [
    "print(\"Pakistan\")\n",
    "print(\"Pakistan\")\n",
    "print(7 / 0)\n",
    "print(\"Pakistan\")\n",
    "print(\"Pakistan\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Name not defined Error:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "ename": "NameError",
     "evalue": "name 'a' is not defined",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mNameError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-5-bca0e2660b9f>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0ma\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mNameError\u001b[0m: name 'a' is not defined"
     ]
    }
   ],
   "source": [
    "print(a)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### index out of range Error:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "ename": "IndexError",
     "evalue": "list index out of range",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mIndexError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-6-25c60e645f7f>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[0ma\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;33m[\u001b[0m\u001b[1;36m2\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m3\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 2\u001b[1;33m \u001b[0ma\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;36m7\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mIndexError\u001b[0m: list index out of range"
     ]
    }
   ],
   "source": [
    "a = [2,3]\n",
    "a[7]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### KeyError:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "ename": "KeyError",
     "evalue": "3",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mKeyError\u001b[0m                                  Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-7-eaa38558199c>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      3\u001b[0m          }\n\u001b[0;32m      4\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 5\u001b[1;33m \u001b[0mmyDict\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;36m3\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mKeyError\u001b[0m: 3"
     ]
    }
   ],
   "source": [
    "myDict = {1: \"Zafar\",\n",
    "         2: \"Abbas\",\n",
    "         }\n",
    "\n",
    "myDict[3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "ename": "ValueError",
     "evalue": "invalid literal for int() with base 10: 'a'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mValueError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-8-233884bacd4e>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m'a'\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mValueError\u001b[0m: invalid literal for int() with base 10: 'a'"
     ]
    }
   ],
   "source": [
    "int('a')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "'int' object is not iterable",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-9-481633a0757e>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mlist\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m2823\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: 'int' object is not iterable"
     ]
    }
   ],
   "source": [
    "list(2823)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['2', '8', '2', '3']"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "list(\"2823\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Solving Errors / Exception Handling"
   ]
  },
  {
   "cell_type": "raw",
   "metadata": {},
   "source": [
    "try:\n",
    "    your code\n",
    "except (err1Class, err2Class,.....):\n",
    "    message show against your errClass\n",
    "\n",
    "else:\n",
    "    message show if exception did not raise\n",
    "\n",
    "finally:\n",
    "    always for this block"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Start ...........\n",
      "You cannot divide with zero\n",
      "End ............\n"
     ]
    }
   ],
   "source": [
    "print(\"Start ...........\")\n",
    "try:\n",
    "    print( 6 / 0 )\n",
    "except ZeroDivisionError:\n",
    "    print(\"You cannot divide with zero\")\n",
    "\n",
    "print(\"End ............\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Start ..........\n",
      "You cannot find data which is not available\n",
      "End ............\n"
     ]
    }
   ],
   "source": [
    "print(\"Start ..........\")\n",
    "try:\n",
    "    a = [2,3]\n",
    "    print(a[7])\n",
    "except IndexError:\n",
    "    print(\"You cannot find data which is not available\")\n",
    "\n",
    "print(\"End ............\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Start ..........\n"
     ]
    },
    {
     "ename": "FileNotFoundError",
     "evalue": "[Errno 2] No such file or directory: 'abc.txt'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mFileNotFoundError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-33-5eb304f3fcf5>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      3\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Start ..........\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      4\u001b[0m \u001b[1;32mtry\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 5\u001b[1;33m     \u001b[0mopen\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m'abc.txt'\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      6\u001b[0m     \u001b[0ma\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;33m[\u001b[0m\u001b[1;36m2\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m3\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      7\u001b[0m     \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0ma\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;36m7\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mFileNotFoundError\u001b[0m: [Errno 2] No such file or directory: 'abc.txt'"
     ]
    }
   ],
   "source": [
    "#  this will not work, do make multiple blocks to solve the issue\n",
    "\n",
    "print(\"Start ..........\")\n",
    "try:\n",
    "    open('abc.txt')\n",
    "    a = [2,3]\n",
    "    print(a[7])\n",
    "    print(7/0)\n",
    "except (IndexError, ZeroDivisionError):\n",
    "    print(\"Please choose select option.\")\n",
    "\n",
    "print(\"End ............\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Start ..........\n",
      "File not found.\n",
      "You choose invalid index number.\n",
      "Zero cannot divide any number.\n",
      "End ............\n"
     ]
    }
   ],
   "source": [
    "#  Multiple blocks of exception handling will work but it will slow down the performance of program execution\n",
    "\n",
    "print(\"Start ..........\")\n",
    "\n",
    "try:\n",
    "    open('abc.txt')\n",
    "except:\n",
    "    print(\"File not found.\")\n",
    "\n",
    "try:\n",
    "    a = [2,3]\n",
    "    print(a[7])\n",
    "except IndexError:\n",
    "    print(\"You choose invalid index number.\")\n",
    "\n",
    "try:\n",
    "    print(7/0)\n",
    "except ZeroDivisionError:\n",
    "    print(\"Zero cannot divide any number.\")\n",
    "\n",
    "print(\"End ............\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "You are trying to solve some invalid problems.....\n"
     ]
    }
   ],
   "source": [
    "#  this will work but it only read the first line and remaining are ignored.\n",
    "\n",
    "try:\n",
    "    open('abc.txt')\n",
    "    a = [2,3]\n",
    "    print(a[7])\n",
    "    print(7/0)\n",
    "except:\n",
    "    print(\"You are trying to solve some invalid problems.....\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Sorry division by zero\n"
     ]
    }
   ],
   "source": [
    "#  this will work but it only read the first line and remaining are ignored.\n",
    "\n",
    "try:\n",
    "    open('abc.txt')\n",
    "    a = [2,3]\n",
    "    print(a[7])\n",
    "    print(7/0)\n",
    "except Exception as e:\n",
    "    print(\"Sorry\", e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    print(7/0)\n",
    "except Exception as a:\n",
    "    print(a)\n",
    "else:\n",
    "    print(\"Your code is running without any error.\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "3.5\n",
      "Your code is running without any error.\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    print(7/2)\n",
    "except Exception as a:\n",
    "    print(a)\n",
    "else:\n",
    "    print(\"Your code is running without any error.\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 41,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "7.0\n",
      "Your code is running without any error.\n",
      "This block will always run.\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    print(7/1)\n",
    "except Exception as a:\n",
    "    print(a)\n",
    "else:\n",
    "    print(\"Your code is running without any error.\")\n",
    "finally:\n",
    "    print(\"This block will always run.\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 42,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'win32'"
      ]
     },
     "execution_count": 42,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import sys\n",
    "sys.platform"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Raise:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 76,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "20"
      ]
     },
     "execution_count": 76,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "class Student():\n",
    "    def __init__(self, age):\n",
    "        if (age < 18 or age > 80):\n",
    "            raise Exception(\"Age Range is 18 to 80\")\n",
    "        self.age = age\n",
    "        \n",
    "obj1 = Student(20)\n",
    "obj1.age\n",
    "        "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 77,
   "metadata": {},
   "outputs": [
    {
     "ename": "Exception",
     "evalue": "Age Range is 18 to 80",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mException\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-77-a10bc34268d4>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mobj1\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mStudent\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m17\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      2\u001b[0m \u001b[0mobj1\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mage\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;32m<ipython-input-76-b23282939419>\u001b[0m in \u001b[0;36m__init__\u001b[1;34m(self, age)\u001b[0m\n\u001b[0;32m      2\u001b[0m     \u001b[1;32mdef\u001b[0m \u001b[0m__init__\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mself\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mage\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      3\u001b[0m         \u001b[1;32mif\u001b[0m \u001b[1;33m(\u001b[0m\u001b[0mage\u001b[0m \u001b[1;33m<\u001b[0m \u001b[1;36m18\u001b[0m \u001b[1;32mor\u001b[0m \u001b[0mage\u001b[0m \u001b[1;33m>\u001b[0m \u001b[1;36m80\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 4\u001b[1;33m             \u001b[1;32mraise\u001b[0m \u001b[0mException\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Age Range is 18 to 80\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      5\u001b[0m         \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mage\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mage\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      6\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mException\u001b[0m: Age Range is 18 to 80"
     ]
    }
   ],
   "source": [
    "obj1 = Student(17)\n",
    "obj1.age"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Assert:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 80,
   "metadata": {},
   "outputs": [],
   "source": [
    "assert(\"hi\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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