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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def store(self, obj_id, title=None, data=None, obj_type=None):
 """ Store data in the autocomplete index. :param obj_id: Either a unique identifier for the object being indexed or the word/phrase to be indexed. :param title: The word or phrase to be indexed. If not provided, the ``obj_id`` will be used as the title. :param data: Arbitrary data to index, which will be returned when searching for results. If not provided, this value will default to the title being indexed. :param obj_type: Optional object type. Since results can be boosted by type, you might find it useful to specify this when storing multiple types of objects. You have the option of storing several types of data as defined by the parameters. At the minimum, you can specify an ``obj_id``, which will be the word or phrase you wish to index. Alternatively, if for instance you were indexing blog posts, you might specify all parameters. """

        if title is None:
            title = obj_id
        if data is None:
            data = title
        obj_type = obj_type or ''

        if self._use_json:
            data = json.dumps(data)

        combined_id = self.object_key(obj_id, obj_type)

        if self.exists(obj_id, obj_type):
            stored_title = self._title_data[combined_id]
            if stored_title == title:
                self._data[combined_id] = data
                return
            else:
                self.remove(obj_id, obj_type)

        self._data[combined_id] = data
        self._title_data[combined_id] = title

        clean_title = ' '.join(self.tokenize_title(title))
        title_score = self.score_token(clean_title)

        for idx, word in enumerate(self.tokenize_title(title)):
            word_score = self.score_token(word)
            position_score = word_score + (self._offset * idx)
            key_score = position_score + title_score
            for substring in self.substrings(word):
                self.database.zadd(self.word_key(substring),
                                   {combined_id: key_score})

        return True