How to Hide Jetpack Boost Admin Menus

function plt_hide_jetpack_boost_menus() {
	//Hide the "Jetpack" menu.
	remove_menu_page('jetpack');
	//Hide the "Jetpack → Boost" menu.
	remove_submenu_page('jetpack', 'jetpack-boost');
}

add_action('admin_menu', 'plt_hide_jetpack_boost_menus', 1001);

Where do I put this code?