How to Hide the "Instagram Widget" Admin Menu

function plt_hide_instagram_widget_by_wpzoom_menus() {
	//Hide the "Settings → Instagram Widget" menu.
	remove_submenu_page('options-general.php', 'wpzoom-instagram-widget');
}

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

Where do I put this code?