Python to Javascript in JavaScript

Question

I want to translate simple Python code to Javascript written in Javascript.
I see 2 options:
1) Simple replace the commands
2) Write a hole compiler
Which should I use and why?

Answer 1

It seems there are already some projects that does that:
→ Transcrypt;
→ Brython;
→ Pyjs;
...

Answer 2

The best version I found was skulpt, but I want to insert my own commands.