Taking first N items from two combined iterators?

Question

I've got two iterables (i1 and i2). Each one is producing items sorted in order of a key, with both iterables using the same key. I want to get the first N items, still sorted by the key, from the combined iterations. If I was willing to completely consume both iterables, I could do:

l = list(i1) + list(i2)
l.sort()
l[:n]

but I know I'm only going to need a small fraction of that. Is there some neat way to do this using just itertools?

Answer 1

See Tim Peters's suggestion to use heapq.merge().