from xml.etree import ElementTree as ET
from xml.dom import minidom


def prettify(elem):
    """将节点转换成字符串，并添加缩进。
    """
    rough_string = ET.tostring(elem, ‘utf-8‘)
    reparsed = minidom.parseString(rough_string)
    return reparsed.toprettyxml(indent="\t")

# 创建根节点
root = ET.Element("famliy")


# 创建节点1
# son1 = ET.Element(‘son‘, {‘name‘: ‘儿1‘})
son1 = root.makeelement(‘son‘, {‘name‘: ‘儿1‘})
# 创建节点2
# son2 = ET.Element(‘son‘, {"name": ‘儿2‘})
son2 = root.makeelement(‘son‘, {"name": ‘儿2‘})

# 创建节点1/2的子节点
# grandson1 = ET.Element(‘grandson‘, {‘name‘: ‘儿11‘})
grandson1 = son1.makeelement(‘grandson‘, {‘name‘: ‘儿11‘})
# grandson2 = ET.Element(‘grandson‘, {‘name‘: ‘儿12‘})
grandson2 = son1.makeelement(‘grandson‘, {‘name‘: ‘儿12‘})

#添加
son1.append(grandson1)
son1.append(grandson2)


# 添加到根节点中
root.append(son1)
root.append(son1)


raw_str = prettify(root)

f = open("xxxoo.xml",‘w‘,encoding=‘utf-8‘)
f.write(raw_str)
f.close()

xml的缩进