Call file / class from ThirdParty folder

Hello, 

guys i have the problem to load file class that i place it at ThirdParty folder,
i try using namescape, require, require_once, include and etc.. but nothing work

example i have this Foo.class

PHP Code:

<?php namespace TP\Tools;

/**
 * 
 */
class Foo
{
    public static function check1(){
        echo "string";
    }
}

?>

Try to call in

PHP Code:

<?php namespace App\Controllers;

use CodeIgniter\Controller;
use App\Models\UserModel;
use TP\Tools\Foo;

class User extends BaseController
{
    private $usermodel;

    public function __construct()
        {
         $this->usermodel = new UserModel();        
        }

        public function index(){
        Foo::check1();
        } 


is it wrong ? pls advise better way to load another file because i cant find it anywhere at user guide..

Thankyou guys for your help