# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def deleteNode(self, node):
        """
        :type node: ListNode
        :rtype: void Do not return anything, modify node in-place instead.
        """
        while node.next != None:
            node.next.val, node.val = node.val, node.next.val
            
            if node.next.next == None:
                node.next = None
            else:
                node = node.next

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def deleteNode(self, node):
        """
        :type node: ListNode
        :rtype: void Do not return anything, modify node in-place instead.
        """
        while node.next != None:
            node.next.val, node.val = node.val, node.next.val
            
            # Is node the penultimate node? If it is, zero out its next
            # pointer.
            if node.next.next == None:
                node.next = None
            else:
                node = node.next

Update solution.py