AttributeError: 'module' object has no attribute 'MultiProposalTarget'

[balabala7776]

loading annotations into memory...
Done (t=16.02s)
creating index...
index created!
('num_images', 82783)
<open file './data/cache/COCO_train2014_gt_roidb.pkl', mode 'rb' at 0x7f9ace4c1e40>
COCO_train2014 gt roidb loaded from ./data/cache/COCO_train2014_gt_roidb.pkl
append flipped images to roidb
loading annotations into memory...
Done (t=9.06s)
creating index...
index created!
('num_images', 40504)
<open file './data/cache/COCO_val2014_gt_roidb.pkl', mode 'rb' at 0x7f995ab03f60>
COCO_val2014 gt roidb loaded from ./data/cache/COCO_val2014_gt_roidb.pkl
append flipped images to roidb
filtered 2138 roidb entries: 246574 -> 244436
add bounding box regression targets
bbox target means:
[[0. 0. 0. 0.]
[0. 0. 0. 0.]]
[0. 0. 0. 0.]
bbox target stdevs:
[[0.1 0.1 0.2 0.2]
[0.1 0.1 0.2 0.2]]
[0.1 0.1 0.2 0.2]
Creating Iterator with 244436 Images
Total number of extracted chips: 955689
Done!
The Iterator has 955776 samples!
Initializing the model...
Traceback (most recent call last):
File "main_train.py", line 91, in
sym = sym_inst.get_symbol_rpn(config) if config.TRAIN.ONLY_PROPOSAL else sym_inst.get_symbol_rcnn(config)
File "/home/yuanyq/Detect_DL/SNIPER/symbols/faster/resnet_mx_101_e2e.py", line 270, in get_symbol_rcnn
rois, label, bbox_target, bbox_weight = mx.sym.MultiProposalTarget(cls_prob=rpn_cls_prob, bbox_pred=rpn_bbox_pred, im_info=im_info,
AttributeError: 'module' object has no attribute 'MultiProposalTarget'