Autoload firebase php-jwt library in CodeIgniter 3

Test.php

<?php defined('BASEPATH') OR exit('No direct script access allowed');

use \Firebase\JWT\JWT;

Class Test extends CI_Controller
{
  public function index()
  {
    
    $key = "example_key";
    $token = array(
        "iss" => "http://example.org",
        "aud" => "http://example.com",
        "iat" => 1356999524,
        "nbf" => 1357000000
      );

     
      $jwt = JWT::encode($token, $key);
    
    echo $jwt;
      
  }
  
}