A one afternoon "proof of I understood" implementation of a hash table in python

hash_table.ipynb

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    "class _dict(object):\n",
    "    \n",
    "    def __init__(self, keys=[], values=[]):\n",
    "        self.keys = list(keys)\n",
    "        self.values = list(values)\n",
    "        if len(self.keys) != len(self.values):\n",
    "            raise ValueError('Not same number of keys and values')\n",
    "        self.indices = []\n",
    "        self.block = []            \n",
    "        self.block_len = len(self.keys)*2\n",
    "        self.set_up_entire_block()\n",
    "    \n",
    "    \n",
    "    def set_up_entire_block(self):\n",
    "        self.block = [[] for x in range(self.block_len)]\n",
    "        for key, value in zip(self.keys, self.values):\n",
    "            index = self.__hash(key)\n",
    "            self.add_to_block(index, key, value)\n",
    "        \n",
    "    def __hash(self, key):\n",
    "        index = sum(map(lambda x:ord(x), str(key)))\n",
    "        index = index % self.block_len\n",
    "        self.indices.append(index)\n",
    "        return index\n",
    "    \n",
    "    def add_to_block(self, index, key, value):\n",
    "        if len(self.block[index]) >= 3:\n",
    "            self.block_len = len(self.keys)*2\n",
    "            self.set_up_entire_block()\n",
    "            return\n",
    "        self.block[index].append((key, value))\n",
    "        \n",
    "    def look_up_key(self, key):\n",
    "        index = self.__hash(key)\n",
    "        for element in self.block[index]:\n",
    "            _key, _value = element\n",
    "            print '|'\n",
    "            if _key == key:\n",
    "                return _value\n",
    "        \n",
    "    def add_key_value_pair(self, key, value):\n",
    "        index = self.__hash(key)\n",
    "        self.indices.append(index)\n",
    "        self.keys.append(key)\n",
    "        self.values.append(value)\n",
    "        self.add_to_block(index, key, value)"
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   "cell_type": "code",
   "execution_count": 76,
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     "output_type": "stream",
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      "|\n"
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       "'c'"
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     "execution_count": 76,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "tryout_dict = _dict(['hallo','lola','bu', 'bar', 'fu', 'baz', 'hallo'], ['a', 'b', 'c', 'd', 1, 2, 3])\n",
    "tryout_dict.add_key_value_pair('per', 3)\n",
    "tryout_dict.look_up_key('bu')"
   ]
  }
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