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  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Interface\n",
    "1. It is achieved in python through **Abstract Base Class**\n",
    "1. If interface is not implemented, interpreter throws error"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "from abc import ABCMeta, abstractmethod, abstractproperty"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "class IRobot(metaclass = ABCMeta):    \n",
    "    @abstractproperty\n",
    "    def data(self):\n",
    "        pass\n",
    "    \n",
    "    @abstractmethod\n",
    "    def speak(self):\n",
    "        pass"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "class Chitti(IRobot):\n",
    "    def __init__(self, value):    # Dunder - Double Underscore\n",
    "        self._data = value\n",
    "       \n",
    "    @property    # Getter\n",
    "    def data(self):\n",
    "        return self._data\n",
    "    \n",
    "    def speak(self):\n",
    "        print(f'{self.data}')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "chitti = Chitti('Speed 1 Tera Hertz, Memory 1 Zetabyte!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Speed 1 Tera Hertz, Memory 1 Zetabyte!\n"
     ]
    }
   ],
   "source": [
    "chitti.speak()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Error"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "class NS5(IRobot):\n",
    "    pass"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "Can't instantiate abstract class NS5 with abstract methods data, speak",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-7-cde518bdbd57>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m()\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mns5\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mNS5\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 NS5 with abstract methods data, speak"
     ]
    }
   ],
   "source": [
    "ns5 = NS5()"
   ]
  }
 ],
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