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   "source": [
    "# Inheritance\n",
    "- powerful feature that facilitates code reuse mimicking real-world phenomena\n",
    "- ability to define a new class (child) that is modified version of an existing class (parent)\n",
    "- can add new methods and properties to a class without modifying the existing class\n",
    "<strong>Limitation(s):</strong><br>\n",
    "    - can make programs difficult to read\n",
    "    - when method is invoked, it is sometimes not clear where to find its definition esp. in a large project relevant code may be scattered among several modules"
   ]
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   "source": [
    "class A(object):\n",
    "    def __init__(self):\n",
    "        self.a = 'A'\n",
    "        \n",
    "    def printMe(self):\n",
    "        print(\"A's info: {}\".format(self.a))\n",
    "\n",
    "class B:\n",
    "    def __init__(self):\n",
    "        self.b = 'B'\n",
    "        \n",
    "    def printMe(self):\n",
    "        print(\"B's info: {}\".format(self.b))\n",
    "        \n",
    "class C(B, A): # what happens if you change order?\n",
    "    def __init__(self):\n",
    "        A.__init__(self)\n",
    "        B.__init__(self)\n",
    "        self.c = 'C'\n",
    "    \n",
    "    def printMe(self):\n",
    "        print(\"A's info: {}\".format(self.a))\n",
    "        print(\"B's info: {}\".format(self.b))\n",
    "        print(\"C's info: {}\".format(self.c))\n",
    "        "
   ]
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  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "A's info: A\n",
      "B's info: B\n",
      "A's info: A\n",
      "B's info: B\n",
      "C's info: C\n"
     ]
    }
   ],
   "source": [
    "obja = A()\n",
    "obja.printMe()\n",
    "objb = B()\n",
    "objb.printMe()\n",
    "objc = C()\n",
    "objc.printMe()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "# How can objects of type C can print their c property info"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## abc module - Abstract Base Classes\n",
    "- allows to define ABCs with abstract methods @abstractmethod decorators"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {
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   "source": []
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