pip‘s dependency resolver does not currently take into account 解决办法

安装torch时，出现如下报错：

ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
onnx 1.7.0 requires six, which is not installed.
onnx 1.7.0 requires typing-extensions>=3.6.2.1, which is not installed.

直接按照他说的，把缺少的包安装就好了：

pip install six
pip install typing-extensions

就可以啦~