use WWW::Mechanize;
use HTML::TokeParser;
my $mech = WWW::Mechanize->new(cookie_jar => undef);
$url="http://www.utsc.utoronto.ca/~registrar/scheduling/timetable";
$prefix = "ANT";
$mech->get($url);

$mech->form_number(2);
$mech->set_visible( [radio => 'summer'] );  # page default anyway
$mech->select( 'course', $prefix );
$mech->click_button( name => 'submit' );

print $mech->content();