def validate_subscription_type(subscription_type)
      unless subscription_type && SUBSCRIBABLE_TYPES.include?(subscription_type)
        raise Fitgem::InvalidArgumentError, "Invalid subscription type (valid values are #{SUBSCRIBABLE_TYPES.join(', ')})"
      end
      true
    end
def validate_subscription_type(subscription_type)
      unless subscription_type && SUBSCRIBABLE_TYPES.include?(subscription_type)
        raise Fitgem::InvalidArgumentError, "Invalid subscription type (valid values are #{SUBSCRIBABLE_TYPES.join(', ')})"
      end
      true
    end
Ensures that the type supplied is valid

 @param [Symbol] subscription_type The type of subscription;
   valid values are (:sleep, :body, :activities, :foods, and
   :all)
 @raise [Fitgem::InvalidArgumentError] Raised if the supplied type
   is not valid
 @return [Boolean]