How to Hide Database Cleaner Admin Menus

function plt_hide_database_cleaner_menus() {
	//Hide the "Meow Apps" menu.
	remove_menu_page('meowapps-main-menu');
	//Hide the "Meow Apps → Dashboard" menu.
	remove_submenu_page('meowapps-main-menu', 'meowapps-main-menu');
	//Hide the "Meow Apps → Database Cleaner" menu.
	remove_submenu_page('meowapps-main-menu', 'dbclnr_settings');
}

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

Where do I put this code?