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

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Using Lists as Stacks
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This manual section was written by Ka-Ping Yee <ping@lfw.org>.
The list methods make it very easy to use a list as a stack, where the
last element added is the first element retrieved ("last-in,
first-out").  To add an item to the top of the stack, use `append()'.
To retrieve an item from the top of the stack, use `pop()' without an
explicit index.  For example:

     >>> stack = [3, 4, 5]
     >>> stack.append(6)
     >>> stack.append(7)
     >>> stack
     [3, 4, 5, 6, 7]
     >>> stack.pop()
     7
     >>> stack
     [3, 4, 5, 6]
     >>> stack.pop()
     6
     >>> stack.pop()
     5
     >>> stack
     [3, 4]