For documentation, see turicreate.text_analytics.count_ngrams().

        ..WARNING:: This function is deprecated, and will be removed in future
        versions of Turi Create. Please use the `text_analytics.count_words`
        function instead.

def _count_ngrams(self, n=2, method="word", to_lower=True, ignore_space=True):
        """
        For documentation, see turicreate.text_analytics.count_ngrams().

        ..WARNING:: This function is deprecated, and will be removed in future
        versions of Turi Create. Please use the `text_analytics.count_words`
        function instead.
        """
        if (self.dtype != str):
            raise TypeError("Only SArray of string type is supported for counting n-grams")

        if (type(n) != int):
            raise TypeError("Input 'n' must be of type int")

        if (n < 1):
            raise ValueError("Input 'n' must be greater than 0")

        if (n > 5):
            warnings.warn("It is unusual for n-grams to be of size larger than 5.")


        # construct options, will extend over time
        options = dict()
        options["to_lower"] = to_lower == True
        options["ignore_space"] = ignore_space == True


        if method == "word":
            with cython_context():
                return SArray(_proxy=self.__proxy__.count_ngrams(n, options))
        elif method == "character" :
            with cython_context():
                return SArray(_proxy=self.__proxy__.count_character_ngrams(n, options))
        else:
            raise ValueError("Invalid 'method' input  value. Please input either 'word' or 'character' ")