I love JavaScript, I get to do all the front end in JS. However, before I moved to front end I did a lot of IT and Infrastructure management. I got to write many scripts in Python and also implemented a back end to monitor and manage services in my previous company.
Python is my favorite programming language because it is easy to write system programs that work without dealing with thinking of how to do it. Nevertheless, I am not really going to recommend on it for any projects. I believe type checking is very essential when working on big projects and there are good programming languages that give features that you don't have in Python or aren't trivial.
Probably, my next programming language will be Go or Elixir. I heard many stories and good feedback on them.