Dimensions M3

Hi, I need to calculate the maximum cubic meters per order. The snippet works perfect. But there is an error in the products with combos: Ex
combo milk x 12. Add the 12 milks separately plus the value declared in the combo. How do I exclude the children of the combo?

https://www.toastedweb.gr/blog/how-to-show-total-dimensions-in-m3-in-cart-checkout-in-woocommerce.html

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