python队列实现

#!/usr/bin/env python3

# Completed implementation of a queue ADT

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

    def is_empty(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)

if __name__ == "__main__":
    q = Queue()
    q.enqueue("hello")
    q.enqueue("dog")
    q.enqueue(3)
    print(q.dequeue())