def to_cf
      props_cf =
        properties.map do |key, value|
          self.class.props[key].to_cf(value)
        end

      common_attributes.merge!(
        'Type' => self.class.aws_name,
        'Properties' => props_cf.to_h
      )
    end
def to_cf
      props_cf =
        properties.map do |key, value|
          self.class.props[key].to_cf(value)
        end

      common_attributes.merge!(
        'Type' => self.class.aws_name,
        'Properties' => props_cf.to_h
      )
    end
CFN stack syntax