      "    def test_end_to_end(self):\n",
      "        hash_table = HashTable(10)\n",
      "\n",
      "        print(\"Test: get on an empty hash table index\")\n",
      "        assert_equal(hash_table.get(0), None)\n",
      "\n",
      "        print(\"Test: set on an empty hash table index\")\n",
      "        hash_table.set(0, 'foo')\n",
      "        assert_equal(hash_table.get(0), 'foo')\n",
      "        hash_table.set(1, 'bar')\n",
 
</s> remove     "        assert_equal(hash_table.get(0), None)\n",
 </s> add     "        assert_raises(KeyError, hash_table.get, 0)\n", </s> remove         assert_equal(hash_table.get(0), None)
 </s> add         assert_raises(KeyError, hash_table.get, 0) </s> remove     "        assert_equal(hash_table.get(10), None)\n",
 </s> add     "        assert_raises(KeyError, hash_table.get, 10)\n", </s> remove     "        assert_equal(hash_table.get(10), None)\n",
 </s> add     "        assert_raises(KeyError, hash_table.get, 10)\n", </s> remove     "        hash_table.remove(-1)\n",
 </s> add     "        assert_raises(KeyError, hash_table.remove, -1)\n",
    "        assert_raises(KeyError, hash_table.get, 0)\n",
      "    def test_end_to_end(self):\n",
      "        hash_table = HashTable(10)\n",
      "\n",
      "        print(\"Test: get on an empty hash table index\")\n",
    "        assert_raises(KeyError, hash_table.get, 0)\n",
      "\n",
      "        print(\"Test: set on an empty hash table index\")\n",
      "        hash_table.set(0, 'foo')\n",
      "        assert_equal(hash_table.get(0), 'foo')\n",
      "        hash_table.set(1, 'bar')\n",
keep keep keep keep replace keep keep keep keep keep
 Update hash map (#104)

Update constraints, test cases, algorithm, code, and tests. 
arrays_strings/hash_map/hash_map_challenge.ipynb