# File lib/RMagick.rb, line 870
    def each_iptc_dataset
        Magick::IPTC.constants.each do |record|
            rec = Magick::IPTC.const_get(record)
            rec.constants.each do |dataset|
                data_field = get_iptc_dataset(rec.const_get(dataset))
                yield(dataset, data_field) unless data_field.nil?
            end
        end
        nil
    end