Навигация между Single для Custom Post Type

Код

<?php
    $next_post = get_adjacent_post( false, '', false);
    $next_post_url = get_the_permalink($next_post);

    $previous_post = get_adjacent_post( false, '', true);
    $previous_post_url = get_the_permalink($previous_post);
?>

<a href="<?php echo $next_post_url;?>">Next post</a>
<a href="<?php echo $previous_post_url;?>">Previous post</a>

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