def extract_pair(items, j, k):
    """Return a 3-tuple that contains two specified items from a list and a new list with all but those items."""
    assert j != k
    assert len(items) >= 2
    assert j < len(items) and k < len(items), "indices not in range: %d and %d must be < %d" % (j, k, len(items))
    p, q = min(j, k), max(j, k)
    return items[p], items[q], items[:p] + items[p+1:q] + items[q+1:]