Reverse Singly Linked List Python

reverse.py

class Node:
  def __init__(self, value, next):
    self.value = value
    self.next = next

  def dump(self):
    print self.value
    if self.next is not None:
      self.next.dump()

def reverse(node):
  # X                      | 3 -> 2 -> 1 -> 0 -> X
  # 3 -> X                 | 2 -> 1 -> 0 -> X
  # 2 -> 3 -> X            | 1 -> 0 -> X
  # 1 -> 2 -> 3 -> X       | 0 -> X
  # 0 -> 1 -> 2 -> 3 -> X  | X
  new_head = None
  while node is not None:
    next = node.next
    node.next = new_head
    new_head = node
    node = next
  return new_head

n0 = Node(0, None)
n1 = Node(1, n0)
n2 = Node(2, n1)
n3 = Node(3, n2)

n3.dump()
# 3 -> 2 -> 1 -> 0

reverse(n3).dump()
# 0 -> 1 -> 2 -> 3