sub enumerate_languages {
   my( $xmltree ) = @_;
   my @nodes = $xmltree->findnodes( '/language' );
   my @langs = map { $_->tagName } @nodes;
   return @langs;
}
sub get_language {
   my( $xmltree, $lang ) = @_;
   my @nodes = $xmltree->findnodes( "/language/$lang/*" );
   my %pairs ;
   for my $node ( @nodes ){
      $pairs{ $node->getAttribute('ID') } = $node->textContent;
   }
   return %pairs;
}