def __init__(self, field):
        self.field = field
        self.previous = None
Get :class:`Playlist` instance for the given ``sp_playlist``. If
dataset/ETHPy150Open enthought/pikos/pikos/filters/on_change.py/OnChange.__init__--crossover with--dataset/ETHPy150Open mopidy/pyspotify/spotify/playlist.py/Playlist._cached