正则表达式缩进XML文件

(?<=<\w+)(.*?)(?=<\/)

<root><element1>value1</element1><element2>value2</element2>
</root>

<root>
 <element1>value1</element1>
 <element2>value2</element2>
</root>

import re

xml = '''<root><element1>value1</element1><element2>value2</element2>
</root>'''

indented_xml = re.sub(r'(?<=<\w+)(.*?)(?=<\/)', r'\n  \g<0>', xml)

print(indented_xml)

<root>
 <element1>value1</element1>
 <element2>value2</element2>
</root>