PEP 572: Python assignment expressions has been accepted

The PEP is here: https://www.python.org/dev/peps/pep-0572/

"This is a proposal for creating a way to assign to variables within an expression using the notation NAME := expr."

> x = y = z = 0 # Equivalent: (x := (y := (z := 0)))

This comment is false. It should say

  x = y = z = 0  # Equivalent: (z := (y := (x := 0)))

"...assigns the single resulting object to each of the target lists, from left to right." https://docs.python.org/3/reference/simple_stmts.html#assign...

Here is a demonstration of the difference:

  >>> class Node: pass
  ...
  >>> node = blue_node = Node()
  >>> red_node = Node()
  >>> node = node.next = red_node
  >>> blue_node.next is red_node
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  AttributeError: Node instance has no attribute 'next'