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Hello
v1.7.1.1. classic
If I want it to show something if a product is in the cart, the following code works:

{$in_cart = 0}
          {foreach from=$cart['products'] item='cart_product'}
          {if $cart_product['id_product'] == $product.id}
          {$in_cart = 1}
          {/if}
          {/foreach}
          {if $in_cart}....{/if}

When I want to check the attributes, the following code does not work for me:

{$in_cart = 0}
          {foreach from=$cart['products'] item='cart_product'}
          {if $cart_product['id_product_attribute'] == $id_attribute}      
          {$in_cart = 1}
          {/if}
          {/foreach}
          {if $in_cart}....{/if}

Because it does not work?
Can you help me?
Thanks