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Question

I'm looking for a way to create an additional view button in the product description.

function et_excerpt_length($length) {
    return 220;
}
add_filter('excerpt_length', 'et_excerpt_length');

/* Add a link  to the end of our excerpt contained in a div for styling purposes and to break to a new line on the page.*/

function et_excerpt_more($more) {
    global $post;
    return '<div class="view-full-post"><a href="'. get_permalink($post->ID) . '" class="view-full-post-btn">View Full Post</a></div>;';
}
add_filter('excerpt_more', 'et_excerpt_more');

I tried many code before but it does not work, can somebody help me, thank you.