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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 trainOn(self, dstream):
 """Train the model on the incoming dstream."""

        self._validate(dstream)

        def update(rdd):
            self._model.update(rdd, self._decayFactor, self._timeUnit)

        dstream.foreachRDD(update)