ref: bfbe4803191725a24151ae04068a18cada3824e4
dir: /sys/src/cmd/python/Demo/xml/elem_count.py/
import sys
from xml.sax import make_parser, handler
class FancyCounter(handler.ContentHandler):
    def __init__(self):
        self._elems = 0
        self._attrs = 0
        self._elem_types = {}
        self._attr_types = {}
    def startElement(self, name, attrs):
        self._elems = self._elems + 1
        self._attrs = self._attrs + len(attrs)
        self._elem_types[name] = self._elem_types.get(name, 0) + 1
        for name in attrs.keys():
            self._attr_types[name] = self._attr_types.get(name, 0) + 1
    def endDocument(self):
        print "There were", self._elems, "elements."
        print "There were", self._attrs, "attributes."
        print "---ELEMENT TYPES"
        for pair in  self._elem_types.items():
            print "%20s %d" % pair
        print "---ATTRIBUTE TYPES"
        for pair in  self._attr_types.items():
            print "%20s %d" % pair
parser = make_parser()
parser.setContentHandler(FancyCounter())
parser.parse(sys.argv[1])