wordpress get related tags

wordpress tags similar to this post

<?php 

// Related Posts Function (call using bones_related_posts(); )
function bones_related_posts() {
	echo '<ul id="bones-related-posts">';
	global $post;
	$tags = wp_get_post_tags($post->ID);
	if($tags) {
		foreach($tags as $tag) { $tag_arr .= $tag->slug . ','; }
        $args = array(
        	'tag' => $tag_arr,
        	'numberposts' => 5, /* you can change this to show more */
        	'post__not_in' => array($post->ID)
     	);
        $related_posts = get_posts($args);
        if($related_posts) {
        	foreach ($related_posts as $post) : setup_postdata($post); ?>
	           	<li class="related_post"><a class="entry-unrelated" href="<?php the_permalink() ?>" title="<?php the_title_attribute(); ?>"><?php the_title(); ?></a></li>
	        <?php endforeach; }
	    else { ?>
            <?php echo '<li class="no_related_post">' . __( 'No Related Posts Yet!', 'bonestheme' ) . '</li>'; ?>
		<?php }
	}
	wp_reset_query();
	echo '</ul>';
} 


 ?>