use Net::DBus;
#get the session bus
my $bus = Net::DBus->session;
my $srv = $bus->get_service("org.gnome");
my $devobj = $srv->get_object("/org/gnome/PowerManager", "org.gnome.PowerManager");

my $cookie = $devobj->Inhibit("Squeezecenter", "Playing");
#.... more code
$devobj->UnInhibit($cookie);