Printing BFS (Binary Tree) in Level Order with Specific Formatting

Question

To begin with, this question is not a dup of this one, but builds on it.

Taking the tree in that question as an example,

    1 
   / \\
  2   3
 /            


        

Answer 1

This is mostly the same code as provided by Alex Martelli except this is modified for python 3.

class Node(object):
  def __init__(self, value, left=None, right=None):
    self.value = value
    self.left = left
    self.right = right

def traverse(rootnode):
  thislevel = [rootnode]
  while thislevel:
    nextlevel = list()
    for n in thislevel:
      print (n.value,' ', end=''),
      if n.left: nextlevel.append(n.left)
      if n.right: nextlevel.append(n.right)
    print(" ")
    thislevel = nextlevel

t = Node(1, Node(2, Node(4, Node(7))), Node(3, Node(5), Node(6)))

traverse(t)