Stack Exchange Function

function ReorderInventory( keys )
local caster = keys.caster
    local target = keys.target
    local slots = {}
    for itemSlot = 0, 5, 1 do

        -- Handle the case in which the caster is removed
        local item
        if IsValidEntity(caster) then
            item = caster:GetItemInSlot( itemSlot )
        end

        if item ~= nil then
            table.insert(slots, itemSlot)
        end
    end

    for k,itemSlot in pairs(slots) do
        caster:SwapItems(itemSlot,k+6)
    end
end

function ReorderStash( keys )
local caster = keys.caster
    local target = keys.target
    local slots = {}
    for itemSlot = 6, 11, 1 do

        -- Handle the case in which the caster is removed
        local item
        if IsValidEntity(caster) then
            item = caster:GetItemInSlot( itemSlot )

        end
        if item ~= nil then
            table.insert(slots, itemSlot)
        end
    end

    for k,itemSlot in pairs(slots) do
        caster:SwapItems(itemSlot,k-6)
    end
end