python-tools was unable to find your machine's python executable.

[biofool]

Docs say that python3 is the default so I expected I did not need a python binary in the path as there is a python setting in the package which was correct.
Resolved by ➜

➜ which python
python not found
➜ which python3
/usr/local/bin/python3
➜ sudo ln -s /usr/local/bin/python{3,}

[peterlada]

This is the way.

[gronk-droid]

this is the way

[chevol]

This fixed it for me, thanks!

[esba1ley]

Also note this comment, showing the differences in the environment picked up by Atom depending on how it is launched under MacOS.