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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 detect_iter(self, det_iter, show_timer=False):
 """ detect all images in iterator Parameters: det_iter : DetIter iterator for all testing images show_timer : Boolean whether to print out detection exec time Returns: list of detection results """

        num_images = det_iter._size
        if not isinstance(det_iter, mx.io.PrefetchingIter):
            det_iter = mx.io.PrefetchingIter(det_iter)
        start = timer()
        detections = self.mod.predict(det_iter).asnumpy()
        time_elapsed = timer() - start
        if show_timer:
            logging.info("Detection time for {} images: {:.4f} sec".format(
                num_images, time_elapsed))
        result = Detector.filter_positive_detections(detections)
        return result