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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 _filter(self, data):
 """ Apply a filter to reduce noisy data. Return the median value of a heap of data. """

        filtered_data = []
        for queue, data in zip(self._raw_data_queues, data):
            queue.append(data)
            filtered_data.append(numpy.median(queue))

        return filtered_data