How to make tool datastore script that doesn't save multiple of the same tool.?

With the data store script i currently have if a player has 2 bronze swords and 3 silver swords and leaves and rejoins the game they will have 2 bronze and 3 silver swords in their inventory when they rejoin. My goal would be to make so when they leave and rejoin they would they would only have one bronze sword and one silver sword when they rejoin. a solution that i have come up with is to put if player.Backpack:FindFirstChild("Bronzesword") then my bronze sword giver script does not give the player the tool thus solving the duplicate problem. The problem with that is i didn't think of this solution until the game got a a lot of visits and a lot of players have multiples of the same tool.

i need to figure out a way to make it so the datastore doesn't save multiple of the same tool or maybe have a script that as soon as a player joins the game it scans through their inventory and checks if they have duplicates.

local rs = game:GetService("ReplicatedStorage")
local ds = game:GetService("DataStoreService")
local store = ds:GetDataStore("saveStore")
local library = rs:WaitForChild("Library")


local dir = {}

local function edit(player, list)
    dir[player.Name] = list
end

local function setup(player, list)
    for i = 1, #list do
        local tool = library:FindFirstChild(list[i])
        if tool then
            local clone = tool:Clone()
            clone.Parent = player.Backpack
        else
            print(list[i] .. " not found")
        end
    end
end

--< player events

game.Players.PlayerAdded:connect(function(player)

local ready = false

    player.CharacterAdded:connect(function(char)

    local bp = player.Backpack
    local data = nil

    if ready == false then
        ready = true

        data = store:GetAsync(player.UserId)

        if data then
            setup(player, data)
            edit(player, data)
        end
    end 

    char.Humanoid.Died:connect(function()
        char.Humanoid:UnequipTools()

        local old = player.StarterGear:GetChildren()
        for i = 1, #old do
            old[i]:Destroy()
        end

        local new = player.Backpack:GetChildren()
        for i = 1, #new do
            new[i].Parent = player.StarterGear
        end     
    end)    

    --< adjuster

    local count = 0

    local function adjust()

    if char.Humanoid.Health > 0 then

        local list = {}

        local equipped = char:FindFirstChildOfClass("Tool")
        if equipped then
            table.insert(list, equipped.Name)
        end 

        local tools = bp:GetChildren()
        for i = 1, #tools do
            table.insert(list, tools[i].Name)
        end

        if count ~= #list then
            edit(player, list)
            count = #list
        end
    end
    end



    bp.ChildAdded:connect(adjust)   
    bp.ChildRemoved:connect(adjust) 

    char.ChildAdded:connect(function(child)
        if child.ClassName == "Tool" then
            adjust()
        end
    end)

    char.ChildRemoved:connect(function(child)
        if child.ClassName == "Tool" then
            adjust()
        end
    end)    

    end)
end)

game.Players.PlayerRemoving:connect(function(player)
    store:SetAsync(player.UserId, dir[player.Name])
    dir[player.Name] = nil
end)


game:BindToClose(function()
    wait(5)
end)