script error! Unique item

[adrianokk]

I made this script that when a player opens the initial box he wins certain items
but I need all the items in the box to be unique items.
but the items are not coming as unique.
TFS 0.3
pokemon

local itens = {
  {2394, 100},
  {12349, 20},
  {17179, 1},
  {17180, 1},
}
local storage = 598
local level = 5
local pos = {x=1000, y=1002, z=7}

function onUse (cid,item,frompos,item2,topos)   
  if getPlayerLevel(cid) >= level then
  if getPlayerStorageValue(cid, storage) == -1 then
     doTeleportThing(cid,pos)
     doPlayerSendTextMessage(cid, 22, "Parabens Voçe Ganhou Sua Box Inicial") -- Msg que ira aparecer
     for i = 1, #itens do
         doPlayerAddItem(cid, itens[i][1], itens[i][2])
     end
     setPlayerStorageValue(cid, storage, 1)
     doSendMagicEffect(getThingPos(cid), 29)
     doPlayerRemoveItem(cid, 10503, 1)
    doSetItemAttribute(item.uid, "unique", itens(cid)) --- ??
  else
     doPlayerSendTextMessage(cid, 22, "Vazio.")
  end
  else
  doPlayerSendCancel(cid,'Voçe Ja Ganhou Sua Box Inicial')
  end
return true
end