nineskeletor/src/Twig/AppExtension.php

<?php
namespace App\Twig;

use Twig\Extension\AbstractExtension;
use Twig\TwigFilter;
use Twig\TwigFunction;
use Ramsey\Uuid\Uuid;

class AppExtension extends AbstractExtension
{
    protected $container;

    public function getFunctions()
    {
        return [
            new TwigFunction('uniqueId', [$this, 'getUniqueId']),
        ];
    }

    public function getUniqueId() {
        return str_replace("-","",Uuid::uuid4());
    }

    public function setContainer($container)
    {
        $this->container = $container;
    }    
}