It doesn't take much effort to cut-and-paste code from another site, and it's considered bad form (at best) NOT to attribute your sources.  If you're going to take code from an alternate source, you should state that up front.

What you posted won't even compile in Perl.  That's because the string ’http://search.cpan.org/’ contains non-standard single quotes (ascii 146) which are often used in documentation, rather than the standard apostrophes "'" (ascii 39).

So my guess is that you got it from some site other than CPAN's version, which uses the apostrophes for that line, but is identical otherwise:

 require LWP::UserAgent;
 
 my $ua = LWP::UserAgent->new;
 $ua->timeout(10);
 $ua->env_proxy;
 
 my $response = $ua->get('http://search.cpan.org/');
 
 if ($response->is_success) {
     print $response->content;  # or whatever
 }
 else {
     die $response->status_line;
 }
[download]

Update:  Okay, I admit I have to agree, mostly, with virtualsue's response below.  I did go overboard with my response, which comes across as a bit harsh/rigid.  Sorry about that.