无法对第 11 行 sample.pl 未定义的值调用方法“text”

问：

use strict;    # safety net
use warnings;  # safety net
use feature 'say'; # a better "print"

use Mojo;
my $dom = Mojo::DOM->new;
my $ua = Mojo::UserAgent->new;
$dom= $ua->get('http://search.cpan.org/faq.html')->res->dom;
my $desc=$dom->at('#u')->text;

当我运行此代码时，发生了上述错误。这是我输入的数据表格，以下网页请参考这个

我想要这样的输出只回答。

   CPAN Search is a search engine for the distributions, modules, docs, and ID's on CPAN. It was conceived and built by Graham Barr as a way to make things easier to navigate. Originally named TUCS [ The Ultimate CPAN Search ] it was later named CPAN Search or Search DOT CPAN.

   If you are having technical difficulties with the site itself, send mail to [email protected] and try to be as detailed as possible in your note describing the problem.

请任何人都可以帮助我