As per the Future Logins documentation section, this code should regenerate a new refresh token that can be saved:

$client = new Client();
$client->login('b17b5ce5-xxxx-yyyy-zzzz-5996a213b834');

$refreshToken = $client->refreshToken();

Currently, the value I retrieve from $client->refreshToken() after logging in with a refresh token, is always the same, so I'm unable to save

This code requires Python 3. Perhaps this should be in the README.

This code is dependent on the hyper module: http://hyper.readthedocs.io/en/latest/