size mismatch for classifier_swap.weight: copying a param of torch.Size([12, 2048]) from checkpoint, where the shape is torch.Size([2, 2048]) in current model.

when I run the test.py, I got the error. How can I solve it ?
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Namespace(acc_report=True, auto_resume=True, backbone='resnet50', batch_size=4, crop_resolution=448, dataset='SHIP', num_workers=0, resize_resolution=512, resume=None, save_suffix=None, swap_num=[7, 7], version='test')
_42315_SHIP
load from ./net_model\_42315_SHIP\weights_0_1026_0.9977_0.9977.pth ...
Traceback (most recent call last):
File "e:/graduation_project/DCL-master/test.py", line 125, in
model.load_state_dict(model_dict)
File "E:\software\anaconda\envs\DCL\lib\site-packages\torch\nn\modules\module.py", line 719, in load_state_dict
self.__class__.__name__, "\n\t".join(error_msgs)))
**RuntimeError: Error(s) in loading state_dict for MainModel:
size mismatch for classifier_swap.weight: copying a param of torch.Size([12, 2048]) from checkpoint, where the shape is torch.Size([2, 2048]) in current model.**