How to Hide SurveyJS Admin Menus

function plt_hide_surveyjs_menus() {
	//Hide the "SurveyJS" menu.
	remove_menu_page('sjs-main-menu');
	//Hide the "SurveyJS → SurveyJS" menu.
	remove_submenu_page('sjs-main-menu', 'sjs-main-menu');
	//Hide the "SurveyJS → Settings" menu.
	remove_submenu_page('sjs-main-menu', 'sjs-settings');
}

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

Where do I put this code?