page_attributes_meta_box

function page_attributes_meta_box( $post ) {
	if ( is_post_type_hierarchical( $post->post_type ) ) :
		$dropdown_args = array(
			'post_type'        => $post->post_type,
			'exclude_tree'     => $post->ID,
			'selected'         => $post->post_parent,
			'name'             => 'parent_id',
			'show_option_none' => __( '(no parent)' ),
			'sort_column'      => 'menu_order, post_title',
			'echo'             => 0,
		);

		/**
		 * Filters the arguments used to generate a Pages drop-down element.
		 *
		 * @since 3.3.0
		 *
		 * @see wp_dropdown_pages()
		 *
		 * @param array   $dropdown_args Array of arguments used to generate the pages drop-down.
		 * @param WP_Post $post          The current post.
		 */
		$dropdown_args = apply_filters( 'page_attributes_dropdown_pages_args', $dropdown_args, $post );
		$pages         = wp_dropdown_pages( $dropdown_args );
		if ( ! empty( $pages ) ) :
			?>
<p class="post-attributes-label-wrapper parent-id-label-wrapper"><label class="post-attributes-label" for="parent_id"><?php _e( 'Parent' ); ?></label></p>
			<?php echo $pages; ?>
			<?php
		endif; // End empty pages check.
	endif;  // End hierarchical check.

	if ( count( get_page_templates( $post ) ) > 0 && get_option( 'page_for_posts' ) != $post->ID ) :
		$template = ! empty( $post->page_template ) ? $post->page_template : false;
		?>
<p class="post-attributes-label-wrapper page-template-label-wrapper"><label class="post-attributes-label" for="page_template"><?php _e( 'Template' ); ?></label>
		<?php
		/**
		 * Fires immediately after the label inside the 'Template' section
		 * of the 'Page Attributes' meta box.
		 *
		 * @since 4.4.0
		 *
		 * @param string  $template The template used for the current post.
		 * @param WP_Post $post     The current post.
		 */
		do_action( 'page_attributes_meta_box_template', $template, $post );
		?>
</p>
<select name="page_template" id="page_template">
		<?php
		/**
		 * Filters the title of the default page template displayed in the drop-down.
		 *
		 * @since 4.1.0
		 *
		 * @param string $label   The display value for the default page template title.
		 * @param string $context Where the option label is displayed. Possible values
		 *                        include 'meta-box' or 'quick-edit'.
		 */
		$default_title = apply_filters( 'default_page_template_title', __( 'Default template' ), 'meta-box' );
		?>
<option value="default"><?php echo esc_html( $default_title ); ?></option>
		<?php page_template_dropdown( $template, $post->post_type ); ?>
</select>
<?php endif; ?>
	<?php if ( post_type_supports( $post->post_type, 'page-attributes' ) ) : ?>
<p class="post-attributes-label-wrapper menu-order-label-wrapper"><label class="post-attributes-label" for="menu_order"><?php _e( 'Order' ); ?></label></p>
<input name="menu_order" type="text" size="4" id="menu_order" value="<?php echo esc_attr( $post->menu_order ); ?>" />
		<?php
		/**
		 * Fires before the help hint text in the 'Page Attributes' meta box.
		 *
		 * @since 4.9.0
		 *
		 * @param WP_Post $post The current post.
		 */
		do_action( 'page_attributes_misc_attributes', $post );
		?>
		<?php if ( 'page' === $post->post_type && get_current_screen()->get_help_tabs() ) : ?>
<p class="post-attributes-help-text"><?php _e( 'Need help? Use the Help tab above the screen title.' ); ?></p>
			<?php
	endif;
	endif;
}