Python in cygwin with puttycyg or mintty - interactive mode without prompt

I finally find the answer at here the last post under that thread.

$ python -i
Python 3.1.1 (r311:74483, Aug 17 2009, 17:02:12) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>

Yay!