解决：ERROR: Cannot uninstall ‘certifi‘. It is a distutils installed project and thus we cannot accurat

当安装 ：pip install rknn_toolkit-1.7.1-cp36-cp36m-linux_x86_64.whl 时，发现以下错误语句，

Installing collected packages: zipp, typing-extensions, six, numpy, threadpoolctl, scipy, protobuf, MarkupSafe, joblib, importlib-metadata, dataclasses, Werkzeug, urllib3, scikit-learn, PyYAML, onnx, Jinja2, itsdangerous, idna, decorator, click, chardet, certifi, sklearn, ruamel.yaml, requests, psutil, ply, Pillow, opencv-python, onnx-tf, networkx, lmdb, h5py, flatbuffers, flask, dill, rknn-toolkit
Attempting uninstall: certifi
Found existing installation: certifi 2016.9.26
ERROR: Cannot uninstall ‘certifi’. 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.

1、错误如下图所示：

2、解决问题：
重新输入命令：

pip install rknn_toolkit-1.7.1-cp36-cp36m-linux_x86_64.whl --ignore-installed

3、成功安装。