my $y=$svg->group(
    id    => 'group_y',
    style => { stroke=>'red', fill=>'green' }
);

$y->circle(cx=>100, cy=>100, r=>50, id=>'circle_in_group_y_1');
# add a circle to the group
$y->circle(cx=>100, cy=>100, r=>50, id=>'circle_in_group_y_2');
$y->comment('This is a comment');
$y->circle(cx=>100, cy=>100, r=>50, id=>'circle_in_group_y_3');
# now render the SVG object, implicitly use svg namespace
print "\nfirst drawing\n";
print $svg->xmlify;