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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 _redis_notifier(state):
 """Notify of configuration update through redis. Arguments: state (_WaffleState):
 Object that contains reference to app and its configstore. """

    tstamp = time.time()
    state._tstamp = tstamp
    conf = state.app.config

    # Notify timestamp
    r = redis.client.StrictRedis()
    r.publish(conf.get('WAFFLE_REDIS_CHANNEL', 'waffleconf'), tstamp)