How to Hide Flex SSL Admin Menus

function plt_hide_flex_ssl_menus() {
	//Hide the "Flex SSL" menu.
	remove_menu_page('flex-ssl');
	//Hide the "Flex SSL → Settings" menu.
	remove_submenu_page('flex-ssl', 'flex-ssl');
	//Hide the "Flex SSL → About" menu.
	remove_submenu_page('flex-ssl', 'flex-ssl-about');
}

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

Where do I put this code?