What codes unlock the treasure book on club penguin?

You really do want a Club Penguin treasure book code right? So do the ones who actually buy the treasure book codes. I am pretty sure they like treasure book items for themselves and will want to use the code themselves. So its useless to ask if somebody can give you a code like that as no one will do so. All the codes they will give out will either be used or fake. Its true, would YOU want to give it out to anybody else if you got such a code?