yapf.yapflib.errors.YapfError: <unknown>:148:4: invalid syntax

[mixed-fish]

(swin_det) E:\s_t\Swin-Transformer-Object-Detection-master>python tools/train.py configs\swin\mask_rcnn_swin_tiny_patch4_window7_mstrain_480-800_adamw_3x_coco.py
fused_weight_gradient_mlp_cuda module not found. gradient accumulation fusion with weight gradient computation disabled.
Traceback (most recent call last):
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf\pytree\pytree_utils.py", line 113, in ParseCodeToTree
tree = parser_driver.parse_string(code, debug=False)
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf_third_party_ylib2to3\pgen2\driver.py", line 188, in parse_string
return self.parse_tokens(tokens, debug)
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf_third_party_ylib2to3\pgen2\driver.py", line 157, in parse_tokens
if p.addtoken(type, value, (prefix, start)):
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf_third_party_ylib2to3\pgen2\parse.py", line 230, in addtoken
return self._addtoken(ilabel, type, value, context)
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf_third_party_ylib2to3\pgen2\parse.py", line 313, in _addtoken
raise ParseError('bad input', type, value, context)
yapf_third_party._ylib2to3.pgen2.parse.ParseError: bad input: type=20, value='<', context=('', (148, 3))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf\yapflib\yapf_api.py", line 206, in FormatCode
tree = pytree_utils.ParseCodeToTree(unformatted_source)
File "D:\py\Anaconda3\envs\swin_det\lib\site-packages\yapf\pytree\pytree_utils.py", line 116, in ParseCodeToTree
ast.parse(code)
File "D:\py\Anaconda3\envs\swin_det\lib\ast.py", line 47, in parse
return compile(source, filename, mode, flags,
File "", line 148
os=<module 'os' from 'D:\py\Anaconda3\envs\swin_det\lib\os.py'>
^
SyntaxError: invalid syntax