请检查我的代码如何为我的新自定义帖子类型创建单独的类别

// 定义自定义帖子类型
function custom_post_type() {
    $args = array(
        'labels' => array(
            'name' => 'Books',
            'singular_name' => 'Book'
        ),
        'public' => true,
        'has_archive' => true,
        'rewrite' => array('slug' => 'books'),
    );
    register_post_type('book', $args);
}
add_action('init', 'custom_post_type');

// 定义自定义类别分类法
function custom_taxonomy() {
    $args = array(
        'labels' => array(
            'name' => 'Genres',
            'singular_name' => 'Genre'
        ),
        'public' => true,
        'rewrite' => array('slug' => 'genre'),
    );
    register_taxonomy('genre', 'book', $args);
}
add_action('init', 'custom_taxonomy');

$args = array(
    'post_type' => 'book',
    'tax_query' => array(
        array(
            'taxonomy' => 'genre',
            'field' => 'slug',
            'terms' => 'fantasy'
        )
    )
);
$books = get_posts($args);

foreach ($books as $book) {
    // 显示帖子信息
    echo '<h2>' . $book->post_title . '</h2>';
    echo '<p>' . $book->post_content . '</p>';
}