WordPress で管理画面にカテゴリIDを表示

http://qiita.com/ashikawa/items/5f94fb5e33da7b023ac8

<?php
function add_category_columns($columns)
{
 $index = 1; // 追加位置
return array_merge(
 array_slice($columns, 0, $index),
 array('id' => 'ID'),
 array_slice($columns, $index)
 );
}
add_filter('manage_edit-category_columns', 'add_category_columns');

function add_category_custom_fields($deprecated, $column_name, $term_id)
{
 if ($column_name == 'id') {
 echo $term_id;
 }
}
add_action('manage_category_custom_column', 'add_category_custom_fields', 10, 3);