How to show co-authors when using the Hybrid theme

coauthors-plus_hybrid.php

<?php
add_filter( 'hybrid_byline', 'my_byline' );

function my_byline( $byline ) {
	global $post;
	
	if ( 'post' == $post->post_type ) {
		$authors_list = '';
		if(function_exists('get_coauthors')) {
			$coauthors = get_coauthors();
			
			$count = 0;
			foreach( $coauthors as $coauthor ) {
				if( $count > 0 ) {
					if( $count < count($coauthors) - 1 ) {
						$authors_list .= ', ';
					} else if ( $count >= count($coauthors) - 1 ) {
						$authors_list .= __(' and ');
					}
				}
				$authors_list .= get_author_posts_url($coauthor->ID);
				$count++;
			}
		} else {
			$authors_list .= get_author_posts_url(get_the_author()->ID);
		}
		return '<p class="byline">By '. $authors_list .' on [entry-published] [entry-edit-link before=" | "]</p>';
	}

	return $byline;
} 
?>