def to_hash
      {}.tap do |hash|
        _attributes.each do |key, value|
          hash[key] = value.respond_to?(:to_hash) ? value.to_hash : value
        end
      end
    end
def to_hash
      {}.tap do |hash|
        _attributes.each do |key, value|
          hash[key] = value.respond_to?(:to_hash) ? value.to_hash : value
        end
      end
    end
The hash representation of this resource. All attributes are serialized
 and any values that respond to +to_hash+ are also serialized.

 @return [Hash]