class Faker::Stripe

def valid_token(card_type: nil)
  valid_tokens = translate('faker.stripe.valid_tokens').keys
  if card_type.nil?
    card_type = sample(valid_tokens).to_s
  else
    unless valid_tokens.include?(card_type.to_sym)
      raise ArgumentError,
            "Valid credit cards argument can be left blank or include #{valid_tokens.join(', ')}"
    end
  end
  fetch("stripe.valid_tokens.#{card_type}")
end