su.pr configuration

Su.pr says:

Unzip and configure supr.php with your account information as shown in the example below. (You can find your account information by clicking on Settings.)

$domain = “http://yourdomain.com/”;
$login = “your_supr_username”;
$apikey = “6b976e43234301b4b4be225180ebdd2bd”;

Where in the supr.php do I enter this?