Modifying Python xml Content

<?xml version="1.0" encoding="UTF-8"?>
<FAMILY
    CATEGORY        =  "Old Category"
    NAME                =  "Old Name"
    >

import xml.etree.ElementTree import parse

xml = parse(file)
root = xml.getroot()
category = root.get('CATEGORY')
name = root.get('NAME')

category = "New Category"
name = "New Name"

xml.write(file)