docs: private void store(PrintWriter writer) throws IOException {
  		for (Entry<String, LinkedHashMap<String, String>> groupEntry : this.groupedMap.entrySet()) {
  			writer.println(StrUtil.format("{}{}{}", CharUtil.BRACKET_START, groupEntry.getKey(), CharUtil.BRACKET_END));
  			for (Entry<String, String> entry : groupEntry.getValue().entrySet()) {
  				writer.println(StrUtil.format("{} {} {}", entry.getKey(), ASSIGN_FLAG, entry.getValue()));
  			}
  		}
  	}