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(python2.1-tut.info)Using Lists as Queues

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Using Lists as Queues
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This manual section was written by Ka-Ping Yee <ping@lfw.org>.
You can also use a list conveniently as a queue, where the first
element added is the first element retrieved ("first-in, first-out").
To add an item to the back of the queue, use `append()'.  To retrieve
an item from the front of the queue, use `pop()' with `0' as the index.
For example:

     >>> queue = ["Eric", "John", "Michael"]
     >>> queue.append("Terry")           # Terry arrives
     >>> queue.append("Graham")          # Graham arrives
     >>> queue.pop(0)
     'Eric'
     >>> queue.pop(0)
     'John'
     >>> queue
     ['Michael', 'Terry', 'Graham']