Finding the last item in a loop

iter_islast.py

def iter_islast(iterable):
    """ iter_islast(iterable) -> generates (item, islast) pairs

    Generates pairs where the first element is an item from the iterable
    source and the second element is a boolean flag indicating if it is the
    last item in the sequence.
    """
    it = iter(iterable)
    prev = it.next()
    for item in it:
        yield prev, False
        prev = item
    yield prev, True