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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 window(self, windowDuration, slideDuration=None):
 """ Return a new DStream in which each RDD contains all the elements in seen in a sliding window of time over this DStream. @param windowDuration: width of the window; must be a multiple of this DStream's batching interval @param slideDuration: sliding interval of the window (i.e., the interval after which the new DStream will generate RDDs); must be a multiple of this DStream's batching interval """

        self._validate_window_param(windowDuration, slideDuration)
        d = self._ssc._jduration(windowDuration)
        if slideDuration is None:
            return DStream(self._jdstream.window(d), self._ssc, self._jrdd_deserializer)
        s = self._ssc._jduration(slideDuration)
        return DStream(self._jdstream.window(d, s), self._ssc, self._jrdd_deserializer)