code: def _etree_py26_write(f, tree):
      
      f.write("<?xml version='1.0' encoding='utf-8'?>\n".encode('utf-8'))
  
      if etree.VERSION[:3] == '1.2':
          def fixtag(tag, namespaces):
              if tag == XML_NS + 'lang':
                  return 'xml:lang', ""
              if '}' in tag:
                  j = tag.index('}') + 1
                  tag = tag[j:]
                  xmlns = ''
              if tag == 'feed':
                  xmlns = ('xmlns', str('http://www.w3.org/2005/Atom'))
                  namespaces['http://www.w3.org/2005/Atom'] = 'xmlns'
              return tag, xmlns
      else:
          fixtag = etree.fixtag
  
      old_fixtag = etree.fixtag
      etree.fixtag = fixtag
      try:
          tree.write(f, encoding=str('utf-8'))
      finally:
          etree.fixtag = old_fixtag
docs: Compatibility workaround for ElementTree shipped with py2.6