到python官方网站，下载macOS 64-bit installer 。
下载完成后双击.pkg文件安装既可
% python3
Python 3.8.3 (v3.8.3:6f8c8320e9, May 13 2020, 16:29:34)
[Clang 6.0 (clang-600.0.57)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
% which python3
/Library/Frameworks/Python.framework/Versions/3.8/bin/python3我这原来的/usr/bin/python3 还是3.7
% /usr/bin/python3
Python 3.7.3 (default, Apr 7 2020, 14:06:47)
[Clang 11.0.3 (clang-1103.0.32.59)] on darwin
Type "help", "copyright", "credits" or "license" for more information.怎样在pycharm里使用？
Setting里面（cmd + ,) search interpreter，选project interpreter
添加成功后
怎样创建virtual environment?
python3 -m venv <path>python 3.8.3有什么新特性？
新添了类型提示。
