code: public byte[] toGzipByteArray() {
  		String sitemap = this.toString();
  		ByteArrayInputStream inputStream = new ByteArrayInputStream(sitemap.getBytes(StandardCharsets.UTF_8));
  		ByteArrayOutputStream outputStream = gzipIt(inputStream);
  		return outputStream.toByteArray();
  	}
docs: Construct sitemap into gzipped file
  
  @return byte array