
class Queue:

  def __init__(self):
    self.items = []

  def isEmpty(self):
    return self.items == []

  def enqueue(self, item):
    self.items.insert(0, item)

  def dequeue(self):
    return self.items.pop()

  def size(self):
    return len(self.items)
  
  def __str__(self):
    res = ''
    for i in self.items:
      res += str(i) + ' | '
    return res