How to Hide Stream Admin Menus

function plt_hide_stream_menus() {
	//Hide "Tools → Scheduled Actions".
	remove_submenu_page('tools.php', 'action-scheduler');

	//Hide "Stream".
	remove_menu_page('wp_stream');
	//Hide "Stream → Stream".
	remove_submenu_page('wp_stream', 'wp_stream');
	//Hide "Stream → Alerts".
	remove_submenu_page('wp_stream', 'edit.php?post_type=wp_stream_alerts');
	//Hide "Stream → Settings".
	remove_submenu_page('wp_stream', 'wp_stream_settings');
}

add_action('admin_menu', 'plt_hide_stream_menus', 11);
Where do I put this code?