Adding dynamic payment buttons to product page (applePay, G Pay, etc.)

[jzier3]

Hi, I am trying to figure out how to add applePay to the product page. Does anyone know how to do this? I have shopPay enabled on my store, and in my liquid file I'm using this: 

{% if additional_checkout_buttons %}
  <p>button available</p>
  <div class="additional-checkout-buttons">
    {{ content_for_additional_checkout_buttons }}
  </div>
{% endif %}

 
I can see the text "Button available" but content_for_additional_checkout_buttons returns an empty div.