How to connect my localhost wordpress site to the internet through a proxy server?

I am trying to connect my localhost site through a proxy by configuring wp-config.php as follow:

define('WP_PROXY_HOST', 'proxy');
define('WP_PROXY_PORT', '8002');
define('WP_PROXY_USERNAME', 'my_user_name');
define('WP_PROXY_PASSWORD', 'my_password');
define('WP_PROXY_BYPASS_HOSTS', 'localhost, www.example.com');

but it didn’t work. did I miss anything?

I am using WAMPserver and wordpress 4.1.1