MemberPress: Set Custom Product Pages

function mepr_is_product_page( $return, $post ) {

    $custom_pages = array( 1, 2, 3 ); //Replace these numbers with the post ID's of the pages

    if( isset( $post ) && in_array( $post->ID, $custom_pages ) ) {

        return true;

    }

    return $return;

} 

add_filter( 'mepr-is-product-page', 'mepr_is_product_page', 10, 2 );