I am trying to create a python function that flips items in a stack. I was provided this code:

Why does this code work?

= = class FlippableStack: def init__(self): ( self.data = DoublyLinkedList(). self.stack_top self.data.header def is_empty(): return len(self) 0 def push(): if stack_top== self.data.header: : self.data.add_first(item) else: self.data.add_last(item) Sa