https://pants.readme.io/docs/installing-pants on this page it talks about

PANTSCMD

, but when I follow this I get

Exception message: No build root detected. Pants detects the build root by looking for at least one file from ['pants', 'BUILDROOT', 'BUILD_ROOT'] in the cwd and its ancestors. If you have none of these files, you can create an empty file in your build root.