Send HTML POST data by Perl LWP

Reference:
How do I send POST data with LWP?

use LWP::UserAgent;

$ua = LWP::UserAgent->new();

$url = "http://www.twse.com.tw/ch/trading/exchange/MI_INDEX/MI_INDEX.php";

$today7 = "1040115";

$response = $ua->post( $url, { 'download' => 'csv',  'qdate' => $today7, 'selectType' => 'ALLBUT0999'} );

$content  = $response->decoded_content();

my $file = 'stocks_twse.csv';

open $FH_o, ">", $file;

print $FH_o $content;

close $FH_o;