mmsegmention运行demo测试报错

ImportError: /home/hadoop-hmart-waimaiups/anaconda3/envs/open-mmlab/lib/python3.7/site-packages/mmcv/_ext.cpython-37m-x86_64-linux-gnu.so: undefined symbol: _ZN6caffe28TypeMeta21_typeMetaDataInstanceISt7complexIdEEEPKNS_6detail12TypeMetaDataEv

ImportError: /home/hadoop-hmart-waimaiups/anaconda3/envs/open-mmlab/lib/python3.7/site-packages/mmcv/_ext.cpython-37m-x86_64-linux-gnu.so: undefined symbol: _ZN6caffe28TypeMeta21_typeMetaDataInstanceISt7complexIdEEEPKNS_6detail12TypeMetaDataEv

查阅资料，当pytorch和torchvision版本不匹配时，也会报undefined symbol: _ZN6caffe28TypeMeta21_的错误。在mmsegmention引导文件中，mmcv安装命令为：

pip install mmcv-full -f https://download.openmmlab.com/mmcv/dist/cu101/torch1.5.0/index.html

而前面创建环境时，使用的为pytorch1.6.0，将命令更换为：

pip uninstall mmcv-full
pip install mmcv-full -f https://download.openmmlab.com/mmcv/dist/cu101/torch1.6.0/index.html