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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 read_items(self, buckets=None, results=15, start=0,item_ids=None):
 """ Returns data from the catalog; also expanded for the requested buckets. This method is provided for backwards-compatibility Args: Kwargs: buckets (list):
 A list of strings specifying which buckets to retrieve results (int):
 An integer number of results to return start (int):
 An integer starting value for the result set Returns: A list of objects in the catalog; list contains additional attributes 'start' and 'total' Example: <catalog - my_songs> [<song - Harmonice Mundi II>] """

        warnings.warn("catalog.read_items() is depreciated. Please use catalog.get_item_dicts() instead.")
        kwargs = {}
        kwargs['bucket'] = buckets or []
        kwargs['item_id'] = item_ids or []
        response = self.get_attribute("read", results=results, start=start, **kwargs)
        rval = ResultList([])
        if item_ids:
            rval.start=0;
            rval.total=len(response['catalog']['items'])
        else:
            rval.start = response['catalog']['start']
            rval.total = response['catalog']['total']
        for item in response['catalog']['items']:
            new_item = None
            # song items
            if 'song_id' in item:
                item['id'] = item.pop('song_id')
                item['title'] = item.pop('song_name')
                request = item['request']
                new_item = song.Song(**util.fix(item))
                new_item.request = request
            # artist item
            elif 'artist_id' in item:
                item['id'] = item.pop('artist_id')
                item['name'] = item.pop('artist_name')
                request = item['request']
                new_item = artist.Artist(**util.fix(item))
                new_item.request = request
            # unresolved item
            else:
                new_item = item
            rval.append(new_item)
        return rval