builtins.TypeError: バイトではなく文字列である必要があります 質問する

スクリプトを Python 2.7 から 3.2 に変換しましたが、バグが発生しました。

# -*- coding: utf-8 -*-
import time
from datetime import date
from lxml import etree
from collections import OrderedDict

# Create the root element
page = etree.Element('results')

# Make a new document tree
doc = etree.ElementTree(page)

# Add the subelements
pageElement = etree.SubElement(page, 'Country',Tim = 'Now', 
                                      name='Germany', AnotherParameter = 'Bye',
                                      Code='DE',
                                      Storage='Basic')
pageElement = etree.SubElement(page, 'City', 
                                      name='Germany',
                                      Code='PZ',
                                      Storage='Basic',AnotherParameter = 'Hello')
# For multiple multiple attributes, use as shown above

# Save to XML file
outFile = open('output.xml', 'w')
doc.write(outFile) 

builtins.TypeError: must be str, not bytes
File "C:\PythonExamples\XmlReportGeneratorExample.py", line 29, in <module>
  doc.write(outFile)
File "c:\Python32\Lib\site-packages\lxml\etree.pyd", line 1853, in lxml.etree._ElementTree.write (src/lxml/lxml.etree.c:44355)
File "c:\Python32\Lib\site-packages\lxml\etree.pyd", line 478, in lxml.etree._tofilelike (src/lxml/lxml.etree.c:90649)
File "c:\Python32\Lib\site-packages\lxml\etree.pyd", line 282, in lxml.etree._ExceptionContext._raise_if_stored (src/lxml/lxml.etree.c:7972)
File "c:\Python32\Lib\site-packages\lxml\etree.pyd", line 378, in lxml.etree._FilelikeWriter.write (src/lxml/lxml.etree.c:89527)