AssertionError: Invalid type

[Jasonshao0123]

When I run python tools/demo.py --source ./inference/images/street.jpg
it appeared:
Traceback (most recent call last):
File "tools/demo.py", line 21, in
from lib.config import cfg
File "/home/zzj/Projects/YOLOP/lib/config/init.py", line 1, in
from .default import _C as cfg
File "/home/zzj/Projects/YOLOP/lib/config/default.py", line 38, in
_C.LOSS.MULTI_HEAD_LAMBDA = None
File "/home/zzj/anaconda3/envs/yolov5/lib/python3.8/site-packages/yacs/config.py", line 155, in setattr
_assert_with_logging(
File "/home/zzj/anaconda3/envs/yolov5/lib/python3.8/site-packages/yacs/config.py", line 521, in _assert_with_logging
assert cond, msg
AssertionError: Invalid type <class 'NoneType'> for key MULTI_HEAD_LAMBDA; valid types = {<class 'list'>, <class 'tuple'>, <class 'int'>, <class 'bool'>, <class 'str'>, <class 'float'>}

I changed the image name .The new name is 'street'.
我实在没能自己解决，麻烦作者看下是哪里出现了问题，应该如何解决呢？

[PigLogic-Cyber]

Try to change '_C.LOSS.MULTI_HEAD_LAMBDA = None' to be '_C.LOSS.MULTI_HEAD_LAMBDA = False', works for me, good luck :-)

[Jasonshao0123]

Try to change '_C.LOSS.MULTI_HEAD_LAMBDA = None' to be '_C.LOSS.MULTI_HEAD_LAMBDA = False', works for me, good luck :-)

thanks 发现是torch版本没对