new_contents: from linked_list import LinkedList
  
  #Stack inherits from LinkedList class
  class Stack(object):
  
      def __init__(self, iterable=None):
          if iterable != None:
              self._linkedList = LinkedList(iterable)
          else:
              self._linkedList = LinkedList()
  
      def push(self, value):
          self._linkedList.insert(value)
  
      def pop(self):
          return self._linkedList.pop()
subject: add stack.py to branch