How to Hide OOW Custom Menu Shortcode Admin Menus

function plt_hide_oowcode_custom_menu_shortcode_menus() {
	//Hide the "OOWCODE" menu.
	remove_menu_page('oow-extensions');
	//Hide the "OOWCODE → OOW Extensions" menu.
	remove_submenu_page('oow-extensions', 'oow-extensions');
	//Hide the "OOWCODE → OOW Menu Shortcode" menu.
	remove_submenu_page('oow-extensions', 'oow-custom-menu-shortcode');
}

add_action('admin_menu', 'plt_hide_oowcode_custom_menu_shortcode_menus', 16);

Where do I put this code?