In comparison to languages like Java or C++, Python has several advantages for coding bitcoin projects:
- Simplified rules of coding allows beginners and experienced alike to code and get results without getting bogged down in formatting etc
- Shell allows on the fly calculations
- Python code is easily read and as such can be edited to suit
- Python can be compiled into an executable or run uncompiled
I suppose in essence, Python is great for small scripts/applications and these small applications often align with difficult Bitcoin protocol mechanisms which are greatly simplified.
The caveat of course is that most Bitcoin Python utilities (Pybitcointools, Pycoin, sx/libitcoin require Python version 2, whereas Python 3 is the current release and, mind-bogglingly, 3.x is not backwards compatible with Python 2
If you want to get a feel for what Python can offer check out either: