How to Hide the "WP Custom Fields Search" Admin Menu

function plt_hide_wp_custom_fields_search_menus() {
	//Hide the "WP Custom Fields Search" menu.
	remove_menu_page('wp_custom_fields_search');
}

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

Where do I put this code?