code: def make_document(self, titlestring):
          
          #root = etree.XML('''<?xml version="1.0"?>\
  #<!DOCTYPE html  PUBLIC '-//W3C//DTD XHTML 1.1//EN'  'http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd'>\
  #<html xml:lang="en-US" xmlns="http://www.w3.org/1999/xhtml" xmlns:ops="http://www.idpf.org/2007/ops">\
  #</html>''')
  
          root = etree.XML('''<?xml version="1.0"?>\
  <!DOCTYPE html>\
  <html xmlns="http://www.w3.org/1999/xhtml">\
  </html>''')
  
          document = etree.ElementTree(root)
          html = document.getroot()
          head = etree.SubElement(html, 'head')
          etree.SubElement(html, 'body')
          title = etree.SubElement(head, 'title')
          title.text = titlestring
          #The href for the css stylesheet is a standin, can be overwritten
          etree.SubElement(head,
                           'link',
                           {'href': 'css/default.css',
                            'rel': 'stylesheet',
                            'type': 'text/css'})
  
          return document
docs: This method may be used to create a new document for writing as xml
          to the OPS subdirectory of the ePub structure.