How to Hide the "BizSwoop Support" Admin Menu

function plt_hide_print_google_cloud_print_gcp_woocommerce_menus() {
	//Hide the "Tools → BizSwoop Support" menu.
	remove_submenu_page('tools.php', 'bizswoop_support');
}

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

Where do I put this code?