Mostrar o modificar un icono en Admin de wordpress, para custom_post_type

gistfile1.php

<?php

/*
Modificar el icono de custom post type en admin wordpress
*/

/**
* registrar el custom post type
*
* @link http://codex.wordpress.org/Function_Reference/register_post_type
*/
protected function register_post_type() {
$labels = array(
	'name'               => __( 'code', 'code-post-type' ),
	'singular_name'      => __( 'Code item', 'code-post-type' ),
	'add_new'            => __( 'Add New Item', 'code-post-type' ),
	// . . .
);


$args = array(

	'menu_icon'       => 'dashicons-welcome-write-blog', // ejemplo: dashicons-portfolio | dashicons-format-chat | etc....
	// visita http://melchoyce.github.io/dashicons/ para ver la lista completa

);