Featured Excerpt Not Displaying After Title

Hi,

I'm using the following code to display the featured excerpt above the featured image and below the post title. The code works and it displays the excerpt, but it also displays the following:

/home/nginx/domains/mysitehere.com/public/wp-content/plugins/code-snippets.back/php/snippet-ops.php(446) : eval()'d code on line 4

add_action('generate_after_entry_title', 'db_single_post_excerpt');
function db_single_post_excerpt() {
if ( is_single() && has_excerpt() ) {
$single_excerpt = apply_filters('the_excerpt', get_post_field('post_excerpt', $post_id));
echo '

';
}
}