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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 saveAsTextFiles(self, prefix, suffix=None):
 """ Save each RDD in this DStream as at text file, using string representation of elements. """

        def saveAsTextFile(t, rdd):
            path = rddToFileName(prefix, suffix, t)
            try:
                rdd.saveAsTextFile(path)
            except Py4JJavaError as e:
                # after recovered from checkpointing, the foreachRDD may
                # be called twice
                if 'FileAlreadyExistsException' not in str(e):
                    raise
        return self.foreachRDD(saveAsTextFile)