I followed the instructions in the README on PyPI, which says:
Installing these plugins will add extra functionality to the language server:
pyls-mypy Mypy type checking for Python 3
After installing pyls-mypy, it pulls in python-language-server (instead of using python-lsp-server) and downgrades jedi. This can confuse many people. Just by accident, I also read the README here on github, which instead says:
Installing these plugins will add extra functionality to the language server:
mypy-ls: MyPy type checking for Python 3.
which correctly uses python-lsp-server.
I guess there will be even more differences than the one mentioned. It might be a good idea to update the README on PyPI?