Return a float for sentiment strength based on the input text.
        Positive values are positive valence, negative value are negative
        valence.

def polarity_scores(self, text):
        """
        Return a float for sentiment strength based on the input text.
        Positive values are positive valence, negative value are negative
        valence.
        """
        # convert emojis to their textual descriptions
        text_token_list = text.split()
        text_no_emoji_lst = []
        for token in text_token_list:
            if token in self.emojis:
                # get the textual description
                description = self.emojis[token]
                text_no_emoji_lst.append(description)
            else:
                text_no_emoji_lst.append(token)
        text = " ".join(x for x in text_no_emoji_lst)

        sentitext = SentiText(text)

        sentiments = []
        words_and_emoticons = sentitext.words_and_emoticons
        for item in words_and_emoticons:
            valence = 0
            i = words_and_emoticons.index(item)
            # check for vader_lexicon words that may be used as modifiers or negations
            if item.lower() in BOOSTER_DICT:
                sentiments.append(valence)
                continue
            if (i < len(words_and_emoticons) - 1 and item.lower() == "kind" and
                    words_and_emoticons[i + 1].lower() == "of"):
                sentiments.append(valence)
                continue

            sentiments = self.sentiment_valence(valence, sentitext, item, i, sentiments)

        sentiments = self._but_check(words_and_emoticons, sentiments)

        valence_dict = self.score_valence(sentiments, text)

        return valence_dict