1.错误背景
在使用pip install rasa-core时出现的问题，问题为：Cannot uninstall greenlet.it is a distuils installed project and thus we cannot accurately determine which file belong to it which would lead to only a partial uninstall.
2.解决方案
pip3 install --ignore-installed greenlet
遇到类似问题可以把greenlet替换为对应模块名