How to Hide SecuPress Free — WordPress Security Admin Menus

function plt_hide_secupress_menus() {
	//Hide "SecuPress".
	remove_menu_page('secupress_scanners');
	//Hide "SecuPress → Scanners".
	remove_submenu_page('secupress_scanners', 'secupress_scanners');
	//Hide "SecuPress → Modules".
	remove_submenu_page('secupress_scanners', 'secupress_modules');
	//Hide "SecuPress → More Security".
	remove_submenu_page('secupress_scanners', 'https://secupress.me/pricing');
}

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

Where do I put this code?