This is a distutils installation project, so we cannot accurately determine the file belonging to the file, which will only cause a partial uninstallation.
Generally, the version you install is a new version, and you need to uninstall the old version, but because you can’t uninstall it completely by directly using pip uninstall+ library name, the most rude way is to delete the old version of the file directly.
Go to anaconda3→Lib→site-packages, find the corresponding old version file, and delete it directly.
For example, the problem I encountered:
ERROR: Cannot uninstall ‘llvmlite’.
site-packages, find the file
llvmlite-0.23.1-py3.6.egg-info, delete it directly and it will be OK