import next() python 2.5

iterator, python, python-2.x

Solution

You can easily provide a definition of this function yourself:

_sentinel = object()
def next(it, default=_sentinel):
    try:
        return it.next()
    except StopIteration:
        if default is _sentinel:
            raise
        return default

Problem

I'm using a slightly altered version of the pairwise recipe from itertools which looks like this ``` def pairwise(iterable): "s -> (s0,s1), (s1,s2), (s2, s3), ..." a, b = tee(iterable) next(b, None) return zip(a, b) ``` Now it turns out I need to run the code with python 2.5 where the next() function throws the following exception: `<type 'exceptions.NameError'>: global name 'next' is not defined` Is there a way to use next() with python 2.5? Or how do I need to modify the function to make it work anyhow?

Original source