3_interview_questions_1.ipynb

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  "cells": [
    {
      "cell_type": "markdown",
      "source": [
        "- How indexing works in sets\n",
        "- Why dict key cant be mutable data types\n",
        "- Enumerate\n",
        "- destructor\n",
        "- dir/isinstance/issubclass\n",
        "- classmethod vs staticmethod\n",
        "- The diamond problem\n",
        "- What’s the meaning of single and double underscores in Python variable and method names\n",
        "- Magic Methods (repr vs str)\n",
        "- How can objects be stored in sets even though they are mutable"
      ],
      "metadata": {
        "id": "8g7s0N6vQFNW"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "s = {21,34,11,56,39}\n",
        "s"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "4YADog27XRE_",
        "outputId": "e763b5c7-4eb1-4d6c-f847-97223c9b5f34"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "{11, 21, 34, 39, 56}"
            ]
          },
          "metadata": {},
          "execution_count": 97
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "d = {(1,2,3):'nitish'}\n",
        "d"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "v1SP9lAYcDns",
        "outputId": "1d72074e-0786-4606-f69f-b0e0bdfbf59f"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "{(1, 2, 3): 'nitish'}"
            ]
          },
          "metadata": {},
          "execution_count": 98
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "d = {[1,2,3]:'nitish'}\n",
        "d"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 187
        },
        "id": "ZL2OZTZDcHv3",
        "outputId": "9cbc1da3-6f53-45d3-8153-b2409e2a08aa"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "error",
          "ename": "TypeError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-99-968dc6d378a3>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0md\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m{\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m3\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m'nitish'\u001b[0m\u001b[0;34m}\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      2\u001b[0m \u001b[0md\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;31mTypeError\u001b[0m: unhashable type: 'list'"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# enumerate\n",
        "# The enumerate() method adds a counter to an iterable and returns it (the enumerate object).\n",
        "L = [('nitish',45),('ankit',31),('ankita',40)]\n",
        "\n",
        "sorted(L,key=lambda x:x[1],reverse=True)"
      ],
      "metadata": {
        "colab": {
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        "id": "SNuZUS02QHgn",
        "outputId": "f4185458-09c5-43e4-da87-bbe52470bb38"
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      "execution_count": null,
      "outputs": [
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          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "[('nitish', 45), ('ankita', 40), ('ankit', 31)]"
            ]
          },
          "metadata": {},
          "execution_count": 112
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "L = [15,21,13,13]\n",
        "sorted(list(enumerate(L)),reverse=True)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "PkKjtmoueMcS",
        "outputId": "c23fa47b-6d24-4255-d348-7230cfb11556"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "[(3, 13), (2, 13), (1, 21), (0, 15)]"
            ]
          },
          "metadata": {},
          "execution_count": 107
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# destructor\n",
        "class Example:\n",
        "\n",
        "  def __init__(self):\n",
        "    print('constructor called')\n",
        "\n",
        "  # destructor\n",
        "  def __del__(self):\n",
        "    print('destructor called')\n",
        "\n",
        "obj = Example()\n",
        "a = obj\n",
        "del obj\n",
        "del a"
      ],
      "metadata": {
        "id": "h7Z7xBiCcF6t",
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "outputId": "b1ab55f1-d0ef-4b43-bd29-5afb1c7176df"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "constructor called\n",
            "destructor called\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# dir\n",
        "\n",
        "class Test:\n",
        "    def __init__(self):\n",
        "        self.foo = 11\n",
        "        self._bar = 23\n",
        "        self.__baz = 23\n",
        "\n",
        "    def greet(self):\n",
        "      print('hello')\n",
        "    \n",
        "t = Test()\n",
        "print(dir(t)) # This gives us a list with the object’s attributes"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
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        "id": "7zpWBxLmc0QF",
        "outputId": "4f3c924c-3fb6-427d-c11e-6cb9b46b7e11"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "['_Test__baz', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_bar', 'foo', 'greet']\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# isinstance\n",
        "\n",
        "class Example:\n",
        "\n",
        "  def __init__(self):\n",
        "    print('hello')\n",
        "\n",
        "obj = Example()\n",
        "\n",
        "isinstance(obj,Example)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "gbqv-qpDjfIf",
        "outputId": "772f72ce-aff6-4fe9-fcc3-af69ebd5b137"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "hello\n"
          ]
        },
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "True"
            ]
          },
          "metadata": {},
          "execution_count": 30
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# issubclass\n",
        "class A:\n",
        "  def __init__(self):\n",
        "    pass\n",
        "\n",
        "class B(A):\n",
        "  pass\n",
        "\n",
        "issubclass(B,A)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "IaoALHTHscQk",
        "outputId": "13617314-bb99-4754-f2e0-ea9b11cc9fea"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "True"
            ]
          },
          "metadata": {},
          "execution_count": 118
        }
      ]
    },
    {
      "cell_type": "markdown",
      "source": [
        "### classmethod\n",
        "- A class method is a method that is bound to the class and not the object of the class.\n",
        "- They have the access to the state of the class as it takes a class parameter that points to the class and not the object instance.\n",
        "- It can modify a class state that would apply across all the instances of the class. For example, it can modify a class variable that will be applicable to all the instances."
      ],
      "metadata": {
        "id": "K1bywWmVC0-5"
      }
    },
    {
      "cell_type": "markdown",
      "source": [
        "### staticmethod\n",
        "A static method does not receive an implicit first argument. A static method is also a method that is bound to the class and not the object of the class. This method can’t access or modify the class state. It is present in a class because it makes sense for the method to be present in class."
      ],
      "metadata": {
        "id": "t-FxUfxODJcy"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "class A:\n",
        "\n",
        "  def normal_m(self):\n",
        "    print('normal method')\n",
        "\n",
        "  @staticmethod\n",
        "  def static_m():\n",
        "    print('static method')\n",
        "  \n",
        "  @classmethod\n",
        "  def class_m(cls):\n",
        "    print('class method')"
      ],
      "metadata": {
        "id": "7ZQAYpyk5Pfs"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "code",
      "source": [
        "a = A()\n",
        "\n",
        "# normal -> object -> callable\n",
        "a.normal_m()\n",
        "# class -> object -> callable\n",
        "a.class_m()\n",
        "# static -> object -> not callable\n",
        "a.static_m()"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "Cglb4jgH_r6s",
        "outputId": "db551854-0680-4179-d93e-df107a77a8fa"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "normal method\n",
            "class method\n",
            "static method\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# static -> class -> callable\n",
        "A.static_m()\n",
        "# class method -> class -> callable \n",
        "A.class_m()\n",
        "# normal -> class -> not callable\n",
        "A.normal_m()"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 241
        },
        "id": "Wg2GbrV9_xlQ",
        "outputId": "9d940e2c-c91e-414e-f557-b5bddf8f6675"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "static method\n",
            "class method\n"
          ]
        },
        {
          "output_type": "error",
          "ename": "TypeError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-94-088d25a52aaf>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      4\u001b[0m \u001b[0mA\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mclass_m\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      5\u001b[0m \u001b[0;31m# normal -> class -> not callable\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 6\u001b[0;31m \u001b[0mA\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mnormal_m\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m: normal_m() missing 1 required positional argument: 'self'"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# Alternate syntax\n",
        "A.normal_m(a)"
      ],
      "metadata": {
        "id": "QZSo-vziBksz"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "markdown",
      "source": [
        "### Class method vs Static Method<br>\n",
        "The difference between the Class method and the static method is:\n",
        "\n",
        "- A class method takes cls as the first parameter while a static method needs no specific parameters.\n",
        "- A class method can access or modify the class state while a static method can’t access or modify it.\n",
        "- In general, static methods know nothing about the class state. They are utility-type methods that take some parameters and work upon those parameters. On the other hand class methods must have class as a parameter.\n",
        "- We use @classmethod decorator in python to create a class method and we use @staticmethod decorator to create a static method in python."
      ],
      "metadata": {
        "id": "aPbAGeiuDjTn"
      }
    },
    {
      "cell_type": "markdown",
      "source": [
        "### When to use the class or static method?\n",
        "- We generally use the class method to create factory methods. Factory methods return class objects ( similar to a constructor ) for different use cases.\n",
        "- We generally use static methods to create utility functions."
      ],
      "metadata": {
        "id": "IxbCxvXPD5CS"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "# The diamond problem\n",
        "class Class1:\n",
        "    def m(self):\n",
        "        print(\"In Class1\")\n",
        "       \n",
        "class Class2(Class1):\n",
        "    def m(self):\n",
        "        print(\"In Class2\")\n",
        " \n",
        "class Class3(Class1):\n",
        "    def m(self):\n",
        "        print(\"In Class3\") \n",
        "        \n",
        "class Class4(Class3, Class2):\n",
        "    pass  \n",
        "     \n",
        "obj = Class4()\n",
        "obj.m()\n",
        "# MRO"
      ],
      "metadata": {
        "id": "UpVqHn5HDrMM",
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "outputId": "30b61a92-8e37-4971-eabb-dd16377105b4"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "In Class3\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "# Double and single score"
      ],
      "metadata": {
        "id": "ZvCjJSt6EMF7"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "code",
      "source": [
        "# repr and other magic/dunder methods\n",
        "\n",
        "a = 'hello'\n",
        "\n",
        "print(str(a))\n",
        "print(repr(a))"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "lJ9pdrNtEOtH",
        "outputId": "ed5a1a6c-ce1d-4ce8-daee-d50f302a544b"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "hello\n",
            "'hello'\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "import datetime\n",
        "\n",
        "a = datetime.datetime.now()\n",
        "b = str(a)\n",
        "\n",
        "print(str(a))\n",
        "print(str(b))\n",
        "\n",
        "print(repr(a))\n",
        "print(repr(b))"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "qbtNfndVNkgv",
        "outputId": "4f02f7dc-d188-4e36-9cb2-9b135b70731b"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "2022-11-26 15:46:52.007475\n",
            "2022-11-26 15:46:52.007475\n",
            "datetime.datetime(2022, 11, 26, 15, 46, 52, 7475)\n",
            "'2022-11-26 15:46:52.007475'\n"
          ]
        }
      ]
    },
    {
      "cell_type": "markdown",
      "source": [
        "### In summary\n",
        "\n",
        "- str is for users -> meant to be more readable\n",
        "- repr is for developers for debugging - > for being unambigous"
      ],
      "metadata": {
        "id": "iLQeyt0WN88O"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "# how objects are stored even though they are mutable\n",
        "# https://stackoverflow.com/questions/31340756/python-why-can-i-put-mutable-object-in-a-dict-or-set\n",
        "class A:\n",
        "  \n",
        "  def __init__(self):\n",
        "    print('constructor')\n",
        "\n",
        "  def hello(self):\n",
        "    print('hello')\n",
        "\n",
        "a = A()\n",
        "a.hello()\n",
        "s = {a}\n",
        "print(s)\n",
        "dir(a)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "gVAOLF4sEUkV",
        "outputId": "a2d1bb93-5600-483e-87f0-96875948b965"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "constructor\n",
            "hello\n",
            "{<__main__.A object at 0x7f4f5f3fd510>}\n"
          ]
        },
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "['__class__',\n",
              " '__delattr__',\n",
              " '__dict__',\n",
              " '__dir__',\n",
              " '__doc__',\n",
              " '__eq__',\n",
              " '__format__',\n",
              " '__ge__',\n",
              " '__getattribute__',\n",
              " '__gt__',\n",
              " '__hash__',\n",
              " '__init__',\n",
              " '__init_subclass__',\n",
              " '__le__',\n",
              " '__lt__',\n",
              " '__module__',\n",
              " '__ne__',\n",
              " '__new__',\n",
              " '__reduce__',\n",
              " '__reduce_ex__',\n",
              " '__repr__',\n",
              " '__setattr__',\n",
              " '__sizeof__',\n",
              " '__str__',\n",
              " '__subclasshook__',\n",
              " '__weakref__',\n",
              " 'hello']"
            ]
          },
          "metadata": {},
          "execution_count": 127
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "class A:\n",
        "  \n",
        "  def __init__(self):\n",
        "    print('constructor')\n",
        "\n",
        "  def __eq__(self):\n",
        "    pass\n",
        "\n",
        "  def __hash__(self):\n",
        "    return 1\n",
        "\n",
        "  def hello(self):\n",
        "    print('hello')\n",
        "\n",
        "a = A()\n",
        "a.hello()\n",
        "s = {a}\n",
        "print(s)\n",
        "\n",
        "dir(a)\n",
        "\n"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "NevwX99-IBKq",
        "outputId": "83f3cf9b-c013-4cd0-d151-f5f6412203ea"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "constructor\n",
            "hello\n",
            "{<__main__.A object at 0x7f4f5f369290>}\n"
          ]
        },
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "['__class__',\n",
              " '__delattr__',\n",
              " '__dict__',\n",
              " '__dir__',\n",
              " '__doc__',\n",
              " '__eq__',\n",
              " '__format__',\n",
              " '__ge__',\n",
              " '__getattribute__',\n",
              " '__gt__',\n",
              " '__hash__',\n",
              " '__init__',\n",
              " '__init_subclass__',\n",
              " '__le__',\n",
              " '__lt__',\n",
              " '__module__',\n",
              " '__ne__',\n",
              " '__new__',\n",
              " '__reduce__',\n",
              " '__reduce_ex__',\n",
              " '__repr__',\n",
              " '__setattr__',\n",
              " '__sizeof__',\n",
              " '__str__',\n",
              " '__subclasshook__',\n",
              " '__weakref__',\n",
              " 'hello']"
            ]
          },
          "metadata": {},
          "execution_count": 133
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "class A:\n",
        "\n",
        "  def __init__(self):\n",
        "    self._var = 10\n",
        "\n",
        "a = A()\n",
        "a._var"
      ],
      "metadata": {
        "id": "3nJqj8h4IdWB",
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "outputId": "a3b8038d-2a4f-4fe2-f239-ade6eb516654"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "10"
            ]
          },
          "metadata": {},
          "execution_count": 121
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "s = {[1,2]}"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 169
        },
        "id": "BYZqiXGzll5W",
        "outputId": "eb225366-d672-4a67-88fd-99d2134f3a05"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "error",
          "ename": "TypeError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-125-abf442ad56c0>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0ms\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m{\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m}\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m: unhashable type: 'list'"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "L = [1,2,3]\n",
        "s = {L}"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 187
        },
        "id": "ZXDsBJ_apicW",
        "outputId": "2f3350e9-982d-42a2-d478-140facf7519c"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "error",
          "ename": "TypeError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-129-fc3c139945bb>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0mL\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m[\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m3\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0ms\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m{\u001b[0m\u001b[0mL\u001b[0m\u001b[0;34m}\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m: unhashable type: 'list'"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "print(L.__hash__)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "khQSIzGKp8Tv",
        "outputId": "34562a4c-23ae-42e0-d99c-2cb687c7ab12"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "None\n"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "hash(1)"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "ZwBQesPWrSCN",
        "outputId": "f4cef974-f796-487c-9b4e-341a2f1f2775"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "1"
            ]
          },
          "metadata": {},
          "execution_count": 138
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "hash('hello')"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "p4pL0CNPrjB-",
        "outputId": "01cacbc6-38b1-4f1d-b05d-48f268c17868"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "4306082800328210013"
            ]
          },
          "metadata": {},
          "execution_count": 139
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "hash((1,2,3,))"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "Jlj1CykIrlbj",
        "outputId": "d208b4c4-2532-4f30-f331-72d3d205c970"
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "2528502973977326415"
            ]
          },
          "metadata": {},
          "execution_count": 140
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [
        "hash([1,2,3])"
      ],
      "metadata": {
        "id": "1weAzIBSrnm2",
        "outputId": "44392ed0-022a-4221-eba2-91682da94aff",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 169
        }
      },
      "execution_count": null,
      "outputs": [
        {
          "output_type": "error",
          "ename": "TypeError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-141-35e31e935e9e>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mhash\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;36m3\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
            "\u001b[0;31mTypeError\u001b[0m: unhashable type: 'list'"
          ]
        }
      ]
    },
    {
      "cell_type": "code",
      "source": [],
      "metadata": {
        "id": "0rqE0HyIrqJq"
      },
      "execution_count": null,
      "outputs": []
    }
  ]
}