title: use commet to some tags in a xml file
body: <p>I read now a xml file, I did particular tag comment but It omitted and then insert comment...</p>
  
  <p>XML:</p>
  
  <pre><code>&lt;book&gt;
    &lt;book-meta&gt;
      &lt;book-id pub-id-type="doi"&gt;1545&lt;/book-id&gt;
  &lt;/book-meta&gt;
  &lt;/book&gt;
  </code></pre>
  
  <p>script: </p>
  
  <pre><code> use strict;
  use XML::Twig;
  open(my $out, '&gt;', 'Output.xml') or die "can't Create stroy file $!\n";
  
  my $story_file = XML::Twig-&gt;new(
                                 twig_handlers =&gt;{
                                          'book-id' =&gt; sub {$_-&gt;set_comment('drop')},
                                          keep_atts_order =&gt; 1,
                                          },
                                          pretty_print =&gt; 'indented',
                                );
  
  $story_file-&gt;parsefile('sample.xml');
  $story_file-&gt;print($out);
  </code></pre>
  
  <p>my output is:</p>
  
  <pre><code>&lt;book&gt;
    &lt;book-meta&gt;&lt;!--drop--&gt;
    &lt;/book-meta&gt;
  &lt;/book&gt;
  </code></pre>
  
  <p>i need out as:</p>
  
  <pre><code>&lt;book&gt;
    &lt;book-meta&gt;
      &lt;!--&lt;book-id pub-id-type="doi"&gt;1545&lt;/book-id&gt;--&gt;
  &lt;/book-meta&gt;
  &lt;/book&gt;
  </code></pre>
  
  <p>what I wrong in this process.... </p>