Initialising Queue in Python

Question

I am trying to code my first Queue class. So far I have this code that seemes to work:

class Queue(list):
    def __init__(self):
        self = []

    def insert(self, x):
        self.append(x)
        return self

    def delete(self):
        if len(self) == 0:
            print "The queue is empty"
        else:
            self.remove(self[0])
            return self

However, I was recomended to rewrite it, and when I try something like this I got wrong results:

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

    def insert(self, x):
        self.items.append(x)

Test:

queue = Queue()
print queue
queue.insert(5)
print queue

Got:

<__main__.Queue instance at 0x0000000002A2F148>
<__main__.Queue instance at 0x0000000002A2F148>

Could you, please, explain me the difference between two approaches and why the second doesn't work (although I saw it on many websites)?

Answer 1

You need need implement either str or repr for your class Queue before printing