Cart ID - Undefined index ID

[carstengrimm]

I am trying to use this class to implement into my shopping cart and according to the examples i am creating entries in my cart and i am trying to use a non-numeric value as 'id' and then later call it in my cart

  $cart->add('hash123',1, [
    'image' =>'some-jpg-123.jpg'
  ]);
// later 
foreach(c::get('cart')->getItems() as $items):
foreach($items as $cart):
<a href="/thumbs/<?php echo byHash($cart['id']) ?>/<?php echo $cart['attributes']['image'] ?>">....</a>
endforeach;
endforeach;

when outputting the raw data, it doesn't have any sort of "id" index... output is for example:

Array
(
    [1lgw886] => Array
        (
            [0] => Array
                (
                    [quantity] => 1
                    [hash] => 8fdd062086410a3f8cc5552c3c4f9363
                    [attributes] => Array
                        (
                            [image] => studio-black-2017-18-41-00.jpg
                        )

                )

        )

)

[Sei Kan]

My mistake, the "id" attribute has been added.