error when running camera_demo.py

python3 camera_demo.py --gpu='0'
2020-01-08 17:00:34.987674: I tensorflow/stream_executor/platform/default/dso_loader.cc:42] Successfully opened dynamic library libcudart.so.10.0
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/home/minh/R2CNN_Tensorflow
Traceback (most recent call last):
File "camera_demo.py", line 16, in
from libs.networks import build_whole_network
File "../libs/networks/build_whole_network.py", line 19, in
from libs.detection_oprations.anchor_target_layer_without_boxweight import anchor_target_layer
File "../libs/detection_oprations/anchor_target_layer_without_boxweight.py", line 15, in
from libs.box_utils.cython_utils.cython_bbox import bbox_overlaps
ImportError: ../libs/box_utils/cython_utils/cython_bbox.so: undefined symbol: _Py_ZeroStruct