请问一下有人使用过Matrix NMS到Faster RCNN模型中吗？将Matrix NMS添加到Faster RCNN的配置文件中时，在eval的时候报出以下错误，请问该如何解决。

loading annotations into memory...
Done (t=0.13s)
creating index...
index created!
Traceback (most recent call last):
  File "tools/train.py", line 140, in 
    main()
  File "tools/train.py", line 136, in main
    run(FLAGS, cfg)
  File "tools/train.py", line 111, in run
    trainer.train(FLAGS.eval)
  File "/home/aistudio/PaddleDetection/ppdet/engine/trainer.py", line 317, in train
    self._eval_with_loader(self._eval_loader)
  File "/home/aistudio/PaddleDetection/ppdet/engine/trainer.py", line 333, in _eval_with_loader
    outs = self.model(data)
  File "/opt/conda/envs/python35-paddle120-env/lib/python3.7/site-packages/paddle/fluid/dygraph/layers.py", line 902, in __call__
    outputs = self.forward(*inputs, **kwargs)
  File "/home/aistudio/PaddleDetection/ppdet/modeling/architectures/meta_arch.py", line 29, in forward
    out = self.get_pred()
  File "/home/aistudio/PaddleDetection/ppdet/modeling/architectures/faster_rcnn.py", line 104, in get_pred
    bbox_pred, bbox_num = self._forward()
  File "/home/aistudio/PaddleDetection/ppdet/modeling/architectures/faster_rcnn.py", line 87, in _forward
    im_shape, scale_factor)
  File "/home/aistudio/PaddleDetection/ppdet/modeling/post_process.py", line 59, in __call__
    bbox_pred, bbox_num, _ = self.nms(bboxes, score, self.num_classes)
  File "/home/aistudio/PaddleDetection/ppdet/modeling/layers.py", line 474, in __call__
    normalized=self.normalized)
  File "/home/aistudio/PaddleDetection/ppdet/modeling/ops.py", line 1094, in matrix_nms
    'matrix_nms')
  File "/opt/conda/envs/python35-paddle120-env/lib/python3.7/site-packages/paddle/fluid/data_feeder.py", line 85, in check_variable_and_dtype
    check_dtype(input.dtype, input_name, expected_dtype, op_name, extra_message)
AttributeError: 'tuple' object has no attribute 'dtype'