Populate webpage textboxes using Perl script.How?

Populate webpage textboxes using Perl script.How?

I've a webpage which has 2 text boxes. When i open the webpage cursor
points to the first textbox. I need to fill these two textboxes and click
on submit. I've written the code, but not working. Any help?
#! /usr/local/bin/perl
use LWP::UserAgent;
use WWW::Mechanize;
my $agent = WWW::Mechanize->new(autocheck => [1]);
my $url =
'http://confluence.broadcom.com/pages/editpage.action?pageId=197431143';
$agent->get($url);
$agent->submit_form(
fields => {
username => $username,
password => $password,
},
button => 'Log In'
);