wishing for a 3-way loop construct

[nilamo]

Couldn't you do this with a with block?  The context manager you define can handle the "first" and "last", while the block is what gets executed in between?

>>> class Pipe:
...   def __init__(self, start, end):
...     self.start = start
...     self.end = end
...   def __enter__(self):
...     self.start(self)
...     return self
...   def __exit__(self, *args):
...     self.end(self)
...
>>> def setup(pipe):
...   pipe.counter = 0
...
>>> def teardown(pipe):
...   print("final count: {0}".format(pipe.counter))
...
>>> with Pipe(setup, teardown) as p:
...   for i in range(4):
...     p.counter += i
...
final count: 6