sub util_remove_duplicates {
  my %hash;
  undef %hash;
  @hash{ref $_[0] eq 'ARRAY' ? @{$_[0]} : @_} = ();
  return keys %hash;
}

##</code><code>##

sub util_remove_duplicates {
  @{$_[0]} = keys %{ { map{$_=>1} @{$_[0]} } };
  return;
}