code: def __save_output(self):
          
          out = zipfile.ZipFile(self.outputfilename, 'w')
  
          for info_zip in self.infile.infolist():
  
              if info_zip.filename in self.templated_files:
                  # Template file - we have edited these.
  
                  # get a temp file
                  streamout = open(get_secure_filename(), "w+b")
                  fname, output_stream = self.output_streams[
                      self.templated_files.index(info_zip.filename)
                  ]
  
                  transformer = get_list_transformer(self.namespaces)
                  remapped_stream = output_stream | transformer
  
                  # write the whole stream to it
                  for chunk in remapped_stream.serialize():
                      streamout.write(chunk.encode('utf-8'))
                      yield True
  
                  # close the temp file to flush all data and make sure we get
                  # it back when writing to the zip archive.
                  streamout.close()
  
                  # write the full file to archive
                  out.write(streamout.name, fname)
  
                  # remove temp file
                  os.unlink(streamout.name)
  
              else:
                  # Copy other files straight from the source archive.
                  out.writestr(info_zip, self.infile.read(info_zip.filename))
  
          # Save images in the "Pictures" sub-directory of the archive.
          for identifier, data in self.images.items():
              out.writestr(PY3O_IMAGE_PREFIX + identifier, data)
  
          # close the zipfile before leaving
          out.close()
          yield True
docs: Saves the output into a native OOo document format.