warn "default_values: " . \%default_values;
    my $self = ref($class) ? bless( \%default_values, ref($class) )
                           : bless( \%default_values, $class );
warn "self: " . $self;

##</code><code>##

    my %h = %default_values;
    my $self = ref($class) ? bless( \%h, ref($class) )
                           : bless( \%h, $class );

##</code><code>##

    my %h = %default_values;
    my $self = bless( \%h, ref($class) || $class );