docs: def load_dale_chall(self):
          """Create the dictionary of words, and grade dictionary, for the Dale-Chall readability test."""
          self.dale_chall_dict = os.path.join(self.base_dir, 'dicts', 'dale_chall.txt')
          with open(self.dale_chall_dict) as words_file:
              data = words_file.read()
          self.dale_chall_words = set(data.splitlines())