跑项目在调用from easyprocess import EasyProcess
遇到报错：

cmd: Union[List[str], str],        
   ^ SyntaxError: invalid syntax

猜测是EasyProcess版本与python版本不对应

pip show EasyProcess

查证一下：

WARNING: pip is being invoked by an old script wrapper. This will fail in a future version of pip.
Please see https://github.com/pypa/pip/issues/5599 for advice on fixing the underlying issue.
To avoid this problem you can invoke Python with '-m pip' instead of running pip directly.
DEPRECATION: Python 2.7 reached the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 is no longer maintained. pip 21.0 will drop support for Python 2.7 in January 2021. More details about Python 2 support in pip can be found at https://pip.pypa.io/en/latest/development/release-process/#python-2-support pip 21.0 will remove support for this functionality.
Name: EasyProcess
Version: 1.1
Summary: Easy to use Python subprocess interface.
Home-page: https://github.com/ponty/easyprocess
Author: ponty
Author-email: UNKNOWN
License: BSD
Location: /home/xxx/anaconda3/envs/xxx/lib/python2.7/site-packages
Requires:
Required-by: PyVirtualDisplay

果然如此。
接下来更换EasyProcess版本，可以从EasyProcess中下载支持所用python的EasyProcess。
然后pip show EasyProcess