Installing cement board prior to putting stone veneer on an exterior wall & it was suggested we add "weep holes" so the moisture can get out. Can you give some input on this & suggestions on how to do this?

Never saw weep holes for concrete siding. Is this Hardie? Weep holes are commonly found behind masonry walls.

I never saw them either until the dealer we are buying the cement board mentioned them--now I see them all over. Behind brick (schools, hospitals) at the exterior base you will notice pieces of rope sticking out. Apparently is to allow moisture to "weep" from behind the brick. Question is--how high does this rope run behind the wall?