Function is_unique:
Defined in module m_vendor (file: /std/modules/m_vendor.c)

put int is_unique() { return 1; } in your object if you wish it
to be kept in a storeroom.  This is most likely because your
object would have variable changes in it.  For example, weapons
can have their wc reduced by wear and you'd rather someone not be
able to purchase a brand new sword after selling a broken one.
