Python is not a good way to start for learning Pawn, they are very different. If your goal is to learn Pawn, just learn Pawn. Start writing plugins and test them (do a lot of searching).
If you're going to use C, C++, Python, etc. for other projects then sure, go ahead and learn one of them but I wouldn't consider them as a necessary stepping stone to Pawn.
There will be similarities in general concepts but you can learn the general concepts in just about any programming language.