When I use :

#!/usr/bin/perl
#
use strict;
use XML::Twig;
#my $twig=XML::Twig->new(pretty_print => 'indented', keep_encoding => 
+1);
my $twig=XML::Twig->new(pretty_print => 'indented');
$twig->parse( '<?xml version="1.0" encoding="UTF-8"?><myxml/>'); 
my $root= $twig->root;  
$root->set_att( 'fille' => 'clémence');
open(PF, "> out.xml") or die "can't open file $!\n";
$twig->print(\*PF);
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I get :

cat out.xml                                                    
<?xml version="1.0" encoding="UTF-8"?>
<myxml fille="clémence"/
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So my question : who has corrupted Clémence ? What have the done her? I know that this subject has soon occured here but without a clear answer.