The docs recommend commands like:
pip install tutor[full]
pip install -e ./tutor[full]
for installing Tutor. These work fine in bash. For zsh,
though, which is now the default on macOS, quotes are
needed, otherwise zsh will interpret the brackets as
special syntax:
pip install "tutor[full]"
pip install -e "./tutor[full]"
Caveat: I have not tested this myself since I don't
own a Mac, but I've read several issue reports to this
effect, such as:
https://github.com/pypa/pipenv/issues/2830#issuecomment-419593199