错误：“无法使用 OpenVINO™ 工具包在 Ubuntu* 20.04 上卸载'PyYAML'”

• 在 Ubuntu 20.04 上安装OpenVINO™工具套件
• Ran demo_squeezenet_download_convert_run.sh
• 遇到以下错误

Collecting pyyaml>=5.4.1
  Downloading PyYAML-5.4.1-cp38-cp38-manylinux1_x86_64.whl (662 kB)
     |████████████████████████████████| 662 kB 3.6 MB/s 
Requirement already satisfied: requests>=2.25.1 in /usr/local/lib/python3.8/dist-packages (from -r /opt/intel/openvino_2021/deployment_tools/demo/../open_model_zoo/tools/downloader/requirements.in (line 2)) (2.26.0)
Requirement already satisfied: urllib3=1.21.1 in /usr/local/lib/python3.8/dist-packages (from requests>=2.25.1->-r /opt/intel/openvino_2021/deployment_tools/demo/../open_model_zoo/tools/downloader/requirements.in (line 2)) (1.26.7)
Requirement already satisfied: charset-normalizer~=2.0.0 in /usr/local/lib/python3.8/dist-packages (from requests>=2.25.1->-r /opt/intel/openvino_2021/deployment_tools/demo/../open_model_zoo/tools/downloader/requirements.in (line 2)) (2.0.6)
Requirement already satisfied: certifi>=2017.4.17 in /usr/lib/python3/dist-packages (from requests>=2.25.1->-r /opt/intel/openvino_2021/deployment_tools/demo/../open_model_zoo/tools/downloader/requirements.in (line 2)) (2019.11.28)
Requirement already satisfied: idna=2.5 in /usr/lib/python3/dist-packages (from requests>=2.25.1->-r /opt/intel/openvino_2021/deployment_tools/demo/../open_model_zoo/tools/downloader/requirements.in (line 2)) (2.8)
Installing collected packages: pyyaml
  Attempting uninstall: pyyaml
    Found existing installation: PyYAML 5.3.1
ERROR: Cannot uninstall 'PyYAML'. It is a distutils installed project and thus we cannot accurately determine which files belong to it which would lead to only a partial uninstall.
Error on or near line 149; exiting with status 1

1. 运行 以下命令以卸载默认的 PyYAML 5.3.1 软件包：
   
    apt-get purge python3-yaml
    
2. 再次运行演示脚本：
   
   .//deployment_tools/demo/demo_squeezenet_download_convert_run.sh