      "        if data is None:\n",
      "            return None\n",
      "        node = Node(data)\n",
      "        if self.head is None:\n",
      "            self.head = Node(data)\n",
      "            return node\n",
      "        curr_node = self.head\n",
      "        while curr_node.next is not None:\n",
      "            curr_node = curr_node.next\n",
      "        curr_node.next = node\n",
 
</s> remove     "            self.head = None\n",
 </s> add     "            self.head = self.head.next\n", </s> remove             self.head = Node(data)
 </s> add             self.head = node </s> remove             self.head = None
 </s> add             self.head = self.head.next </s> remove    "pygments_lexer": "ipython3",
   "version": "3.5.0"
 </s> add    "pygments_lexer": "ipython2",
   "version": "2.7.12" </s> remove     "version": 3
 </s> add     "version": 2
    "            self.head = node\n",
      "        if data is None:\n",
      "            return None\n",
      "        node = Node(data)\n",
      "        if self.head is None:\n",
    "            self.head = node\n",
      "            return node\n",
      "        curr_node = self.head\n",
      "        while curr_node.next is not None:\n",
      "            curr_node = curr_node.next\n",
      "        curr_node.next = node\n",
keep keep keep keep replace keep keep keep keep keep
 Fix #173: Bugs in linked list append and delete methods (#184) 
linked_lists/linked_list/linked_list_solution.ipynb