best way to calculate tax python

1from xml.etree import cElementTree as ElementTree
2
3class XmlListConfig(list):
4    def __init__(self, aList):
5        for element in aList:
6            if element:
7                # treat like dict
8                if len(element) == 1 or element[0].tag != element[1].tag:
9                    self.append(XmlDictConfig(element))
10                # treat like list
11                elif element[0].tag == element[1].tag:
12                    self.append(XmlListConfig(element))
13            elif element.text:
14                text = element.text.strip()
15                if text:
16                    self.append(text)
17
18
19class XmlDictConfig(dict):
20    '''
21    Example usage:
22
23    >>> tree = ElementTree.parse('your_file.xml')
24    >>> root = tree.getroot()
25    >>> xmldict = XmlDictConfig(root)
26
27    Or, if you want to use an XML string:
28
29    >>> root = ElementTree.XML(xml_string)
30    >>> xmldict = XmlDictConfig(root)
31
32    And then use xmldict for what it is... a dict.
33    '''
34    def __init__(self, parent_element):
35        if parent_element.items():
36            self.update(dict(parent_element.items()))
37        for element in parent_element:
38            if element:
39                # treat like dict - we assume that if the first two tags
40                # in a series are different, then they are all different.
41                if len(element) == 1 or element[0].tag != element[1].tag:
42                    aDict = XmlDictConfig(element)
43                # treat like list - we assume that if the first two tags
44                # in a series are the same, then the rest are the same.
45                else:
46                    # here, we put the list in dictionary; the key is the
47                    # tag name the list elements all share in common, and
48                    # the value is the list itself 
49                    aDict = {element[0].tag: XmlListConfig(element)}
50                # if the tag has attributes, add those to the dict
51                if element.items():
52                    aDict.update(dict(element.items()))
53                self.update({element.tag: aDict})
54            # this assumes that if you've got an attribute in a tag,
55            # you won't be having any text. This may or may not be a 
56            # good idea -- time will tell. It works for the way we are
57            # currently doing XML configuration files...
58            elif element.items():
59                self.update({element.tag: dict(element.items())})
60            # finally, if there are no child tags and no attributes, extract
61            # the text
62            else:
63                self.update({element.tag: element.text})
64