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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 find_by_ids(ids, connection=None, page_size=100, page_number=0, sort_by=DEFAULT_SORT_BY, sort_order=DEFAULT_SORT_ORDER):
 """ List playlists by specific IDs. """

        ids = ','.join([str(i) for i in ids])
        return pybrightcove.connection.ItemResultSet('find_playlists_by_ids',
            Playlist, connection, page_size, page_number, sort_by, sort_order,
            playlist_ids=ids)