Module
itertools

Functional tools for creating and using iterators.

Infinite iterators: count([n]) --> n, n+1, n+2, ... cycle(p) --> p0, p1, ... plast, p0, p1, ... repeat(elem [,n]) --> elem, elem, elem, ... endlessly or up to n times

Iterators terminating on the shortest input sequence: izip(p, q, ...) --> (p[0], q[0]), (p[1], q[1]), ... ifilter(pred, seq) --> elements of seq where pred(elem) is True ifilterfalse(pred, seq) --> elements of seq where pred(elem) is False islice(seq, [start,] stop [, step]) --> elements from seq[start:stop:step] imap(fun, p, q, ...) --> fun(p0, q0), fun(p1, q1), ... starmap(fun, seq) --> fun(*seq[0]), fun(*seq[1]), ... tee(it, n=2) --> (it1, it2 , ... itn) splits one iterator into n chain(p, q, ...) --> p0, p1, ... plast, q0, q1, ... takewhile(pred, seq) --> seq[0], seq[1], until pred fails dropwhile(pred, seq) --> seq[n], seq[n+1], starting when pred fails groupby(iterable[, keyfunc]) --> sub-iterators grouped by value of keyfunc(v)