creating subscription with laravel cashier

Documentation lists this example:

$user = User::find(1);

$user->newSubscription('main', 'monthly')->create($creditCardToken);

The create method will begin the subscription as well as update your database with the customer ID and other relevant billing information.

Does anyone know where do I get $creditCardToken from? I am using Braintree and perhaps this example is for Stripe?

via Chebli Mohamed