Python Decorators..ipynb

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    "def hello():\n",
    "    print ('Hello!')\n",
    "\n",
    "greet = hello"
   ]
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      "Hello!\n"
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    "greet()"
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   "source": [
    "def hello(name):\n",
    "    print ('Hey this is the hello parent function!!')\n",
    "    \n",
    "    def greet():\n",
    "        return '\\t Hey this is the greet function inside Hello func!!'\n",
    "    def welcome():\n",
    "        return '\\t Hey this is the welcome function inside Hello func!!'\n",
    "    \n",
    "    if name=='Jit':\n",
    "        return greet\n",
    "    else:\n",
    "        return welcome"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hey this is the hello parent function!!\n"
     ]
    }
   ],
   "source": [
    "my_func= hello('Jit')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<function __main__.hello.<locals>.greet()>"
      ]
     },
     "execution_count": 6,
     "metadata": {},
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   "source": [
    "my_func"
   ]
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   "cell_type": "code",
   "execution_count": 7,
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     "data": {
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       "'\\t Hey this is the greet function inside Hello func!!'"
      ]
     },
     "execution_count": 7,
     "metadata": {},
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   "source": [
    "my_func()"
   ]
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  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [],
   "source": [
    "#Decorator Creation"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [],
   "source": [
    "def func_needs_decoration():\n",
    "    print('I need to be decorated!!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "def new_decorator(pass_func_that_needs_decoration):\n",
    "    \n",
    "    def wrap_func():\n",
    "        print('Some code that will come before original!')\n",
    "        pass_func_that_needs_decoration()\n",
    "        print('Some code that will come after original!')\n",
    "    return wrap_func"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_new_func= func_needs_decoration\n",
    "decorated_func= new_decorator(my_new_func)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I need to be decorated!!\n"
     ]
    }
   ],
   "source": [
    "my_new_func()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [],
   "source": [
    "decorated_func= new_decorator(func_needs_decoration) "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Some code that will come before original!\n",
      "I need to be decorated!!\n",
      "Some code that will come after original!\n"
     ]
    }
   ],
   "source": [
    "decorated_func()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Some code that will come before original!\n",
      "I need to be decorated!!\n",
      "Some code that will come after original!\n"
     ]
    }
   ],
   "source": [
    "deco= new_decorator(my_new_func)\n",
    "deco()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "#Syntax on how to add new decorator to existing function."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [],
   "source": [
    "@new_decorator\n",
    "def func_needs_decoration(): \n",
    "    print('I need to be decorated!!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Some code that will come before original!\n",
      "I need to be decorated!!\n",
      "Some code that will come after original!\n"
     ]
    }
   ],
   "source": [
    "func_needs_decoration()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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