code: def _get_ondisk_chapter(self, book_name, book_chapter):
          
          # First attempt to look up the chapter on the disk
          verses_list = []
          filename = os.path.expanduser("~/.diyr/{}/{}").format(
              book_name,
              book_chapter)
          if os.path.isfile(filename):
              # Read the file into a list
              try:
                  f = open(filename)
              except OSError as e:
                  logging.error("Could not read {}".format(filename))
                  return ["ERROR! Could not read {}".format(filename)]
  
              for line in f.readlines():
                  verses_list.append(line)
  
              return verses_list
          else:
              # If the file is not cached, raise an Exception
              raise Exception("The file {} is not cached!".format(filename))
docs: Retrieves the given bible chapter from it's on disk location.
          Currently, the location `~/.diyr/<book_name>/` is supported