In Sublime, we have an easy and convent way to run Python or almost any language for that matter using ⌘ + b (or ctrl + b)
Download and Install package here: https://atom.io/packages/script
To execute the python command in atom use the below shortcuts:
For Windows/Linux, it's SHIFT + Ctrl + B OR Ctrl + SHIFT + B
If you're on Mac, press ⌘ + I