How To Pretty-Print a Python ElementTree Structure

ElementTree doesn’t support pretty-printing XML. lxml does, but isn’t installed on our system. minidom‘s toprettyxml() is seriously fucked up. What to do? Turned out PyXML was installed, so I took some advice from here and came up with this function, which takes an ET node and returns a pretty-printed string:

import xml.etree.ElementTree as ET
from xml.dom.ext.reader import Sax2
from xml.dom.ext import PrettyPrint
from StringIO import StringIO
def prettyPrintET(etNode):
    reader = Sax2.Reader()
    docNode = reader.fromString(ET.tostring(etNode))
    tmpStream = StringIO()
    PrettyPrint(docNode, stream=tmpStream)
    return tmpStream.getvalue()