my $cart = Google::Checkout::Cart;
   $cart->add_item( 
       name => 'Bill',
       description => 'a pal',
       price => 'priceless', quantity => 2
   );
   $cart->post( 
      merchant_auth_encoded =>         
        q[MTIzNDU2Nzg5MDpIc1lYRm9aZkhBcXlMY0NSWWVIOHFR]
   );