How to Hide the "Get My Sina Weibo" Admin Menu

function plt_hide_get_my_sina_weibo_menus() {
	//Hide the "Settings → Get My Sina Weibo" menu.
	remove_submenu_page('options-general.php', 'get-my-sina-weibo/get-my-sina-weibo.php');
}

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

Where do I put this code?