def tokenize_sentences(self, untokenized_string: str):
        """Tokenize sentences by reading trained tokenizer and invoking
        ``PunktSentenceTokenizer()``.
        :type untokenized_string: str
        :param untokenized_string: A string containing one of more sentences.
        :rtype : list of strings
        """
        # load tokenizer
        assert isinstance(untokenized_string, str), \
            'Incoming argument must be a string.'

        if self.language == 'latin':
            self.models_path = self._get_models_path(self.language)
            try:
                self.model = open_pickle(
                    os.path.expanduser(os.path.join(self.models_path, 'latin_punkt.pickle')))
            except FileNotFoundError as err:
                raise type(err)(TokenizeSentence.missing_models_message + self.models_path)
            tokenizer = self.model
            tokenizer._lang_vars = self.lang_vars
        elif self.language == 'greek': # Workaround for regex tokenizer
            self.sent_end_chars=GreekLanguageVars.sent_end_chars
            self.sent_end_chars_regex = '|'.join(self.sent_end_chars)
            self.pattern = rf'(?<=[{self.sent_end_chars_regex}])\s'
        else:
            tokenizer = open_pickle(self.tokenizer_path)
            tokenizer = self._setup_tokenizer(tokenizer)

        # mk list of tokenized sentences
        if self.language == 'latin':
            return tokenizer.tokenize(untokenized_string)
        elif self.language == 'greek':
            return re.split(self.pattern, untokenized_string)
        else:
            tokenized_sentences = [sentence for sentence in
                                   tokenizer.sentences_from_text(untokenized_string,
                                                                 realign_boundaries=True)]
            return tokenized_sentences
Tokenize sentences by reading trained tokenizer and invoking
        ``PunktSentenceTokenizer()``.
        :type untokenized_string: str
        :param untokenized_string: A string containing one of more sentences.
        :rtype : list of strings