cmb2 metabox

$group_field_id = $box->add_field( array(
		'id'          => $prefix . 'group',
		'type'        => 'group',
		'options'     => array(
			'group_title'   => ($box->title) ? $box->title : __( 'Snippet {#}', 'cmb2' ), // {#} gets replaced by row number
			'add_button'    => __( 'Add Another Snippet', 'cmb2' ),
			'remove_button' => __( 'Remove Snippet', 'cmb2' ),
			// 'closed'     => true,
		),
	) );
$box->add_group_field( $group_field_id, array(
		'name'       => __( 'Title', 'cmb2' ),
		'id'         => 'title',
		'type'       => 'text',
	) );

	$box->add_group_field( $group_field_id, array(
		'name'        => __( 'Code', 'cmb2' ),
		'description' => __( 'Enter the code for the snippet', 'cmb2' ),
		'id'          => 'code',
		'type'        => 'textarea_code',
	) );