code: def sentences(ctx, input, output):
      
      log.info('chemdataextractor.read.elements')
      log.info('Reading %s' % input.name)
      doc = Document.from_file(input)
      for element in doc.elements:
          if isinstance(element, Text):
              for raw_sentence in element.raw_sentences:
                  output.write(raw_sentence.strip())
                  output.write(u'\n')
docs: Read input document, and output sentences.