maaaats parent
So this transpiler makes ES6 code and then Babel makes it runnable on most browsers, or does it leverage Babel in making JS code in the first place?
The former, it translates Python 3.5 syntax and some of the core semantics to ES6+ JavaScript and then BabelJS is used to transpile that ES6 JS to ES5. All this retaining a sourcemap that maps back to the original Python sources.
It does all without the need for nodejs (even if it can be used of course), it uses an embedded js interpreter.
Going by the docs, it's a Python 3 to ES6 transpiler.