Index function for iterables. Particularly handy when dealing with infinite iterables.

iindex.py

from itertools import islice


def iindex(iterable, index):
    """ Indexing for all iterables.  Translates to iterable[index]. """
    return next(islice(iterable, index, index + 1))


def example():
    def fibs():
        x, y = 0, 1
        yield x
        yield y
        while True:
            x, y = y, x + y
            yield y
    # Get the 100th fibonacci number
    iindex(fibs(), 100)