How to Hide the "Advanced Editor Tools" Admin Menu

function plt_hide_tinymce_advanced_menus() {
	//Hide the "Settings → Advanced Editor Tools" menu.
	remove_submenu_page('options-general.php', 'tinymce-advanced');
}

add_action('admin_menu', 'plt_hide_tinymce_advanced_menus', 11);

Where do I put this code?