my $tree = XML::TreeBuilder->new_from_content(<<EOF);
?xml version="1.0"?> 
<root> 
  <aaa id='test'> 
    <bbb/> 
  </aaa> 
</root> 
EOF

my $elem = $tree->look_down(id => 'text');
$elem->this;
$elem->that;
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