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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 select_top_predictions(self, predictions):
 """ Select only predictions which have a `score` > self.confidence_threshold, and returns the predictions in descending order of score Arguments: predictions (BoxList):
 the result of the computation by the model. It should contain the field `scores`. Returns: prediction (BoxList):
 the detected objects. Additional information of the detection properties can be found in the fields of the BoxList via `prediction.fields()` """

        scores = predictions.get_field("scores")
        keep = torch.nonzero(scores > self.confidence_threshold).squeeze(1)
        predictions = predictions[keep]
        scores = predictions.get_field("scores")
        _, idx = scores.sort(0, descending=True)
        return predictions[idx]