ImportError libtorch_python.so: undefined symbol

Hi!
I’m trying to use the Pytorch model in C++.
I downloaded LibTorch(cxx11 ABI) additionally, and used it by adding its path.

If I use PyImport_Import function, The error message is as follows

Traceback (most recent call last):
  File "/home/sensor/Documents/test/build/segmentation.py", line 1, in <module>
    import torch, torchvision
  File "/usr/local/lib/python3.6/dist-packages/torch/__init__.py", line 190, in <module>
    from torch._C import *
ImportError: /usr/local/lib/python3.6/dist-packages/torch/lib/libtorch_python.so: undefined symbol: _ZN5torch11distributed3rpc8RpcAgent12getDebugInfoEv

How to solve this error??

*my environment
ubuntu : 18.04
CUDA : 10.2
python : 3.6.9
torch : 1.7.0
torchvision : 0.8.0