from __future__ import print_function

from xml.etree.ElementTree import *

xml_text="""<?xml version="1.0"?>
<real:actors xmlns:fictional="http://characters.example.com"
        xmlns:real="http://people.example.com">
    <real:actor>
        <real:name>John Cleese</real:name>
        <fictional:character>Lancelot</fictional:character>
        <fictional:character>Archie Leach</fictional:character>
    </real:actor>
    <real:actor>
        <real:name>Eric Idle</real:name>
        <fictional:character>Sir Robin</fictional:character>
        <fictional:character>Gunther</fictional:character>
        <fictional:character>Commander Clement</fictional:character>
    </real:actor>
</real:actors>"""

ns = {'real_person': 'http://people.example.com',
      'role': 'http://characters.example.com'}

def printLastRoles(root):
    lastRoles = root.findall('./real_person:actor/role:character[last()]', ns)
    print('Found', len(lastRoles), 'last roles:')
    for lc in lastRoles:
        print('-->', lc.text)

print('\nUsing fromstring')
root = fromstring(xml_text)
printLastRoles(root)

print('\nUsing XMLParser and TreeBuilder')
def myParser():
    """ET XML parserer that stores tree in ElementWithDelegate instances"""
    return XMLParser(target=TreeBuilder())

root = fromstring(xml_text, parser=myParser())
printLastRoles(root)

print('\nUsing XMLParser and TreeBuilder with Element subclass')

class ElementSubclass(Element):
    def __init__(self, *args, **kwargs):
        Element.__init__(self, *args, **kwargs)
        self.my_attribute = None
        
def myParser():
    """ET XML parserer that stores tree in ElementWithDelegate instances"""
    return XMLParser(target=TreeBuilder(element_factory=ElementSubclass))

root = fromstring(xml_text, parser=myParser())
printLastRoles(root)