import xml.etree.ElementTree as ET
解析XML字符串或文件
xml_data = '''

'''
root = ET.fromstring(xml_data)
为person节点动态添加新属性
person = root.find('person')
person.set('name', 'Alice')
person.set('age', '25')
打印修改后的XML
print(ET.tostring(root, encoding='unicode'))

// 创建一个XML文档（模拟）
const parser = new DOMParser();
let xmlDoc = parser.parseFromString(
  ``, "text/xml"
);
// 获取目标元素
const person = xmlDoc.querySelector("person");
// 动态添加属性
person.setAttribute("city", "Beijing");
person.setAttribute("job", "Engineer");
// 序列化回字符串
const serializer = new XMLSerializer();
console.log(serializer.serializeToString(xmlDoc));

import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.*;
// 解析XML
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new InputSource(new StringReader(xmlString)));
// 获取元素并添加属性
Element person = (Element) doc.getElementsByTagName("person").item(0);
person.setAttribute("email", "alice@example.com");
person.setAttribute("level", "senior");
// 输出修改后的XML
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
StringWriter writer = new StringWriter();
transformer.transform(new DOMSource(doc), new StreamResult(writer));
System.out.println(writer.toString());