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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 stop(self, stopSparkContext=True, stopGraceFully=False):
 """Stop processing streams. :param stopSparkContext: stop the SparkContext (NOT IMPLEMENTED) :param stopGracefully: stop gracefully (NOT IMPLEMENTED) """

        while self._on_stop_cb:
            cb = self._on_stop_cb.pop()
            log.debug('calling on_stop_cb {}'.format(cb))
            cb()

        IOLoop.current().stop()

        StreamingContext._activeContext = None