different behavior from idle/pycharm and shell

[kiuhnm03 at yahoo.it]

Consider this code:

---
from ctypes import *

user32 = windll.user32
user32.MessageBoxA(0, 'ok', 'ok', 0)
---

If I run it in idle or from pycharm, the messagebox shows 'o' instead of 'ok', but if I run it from shell, it shows 'ok' like it should.
The same happens with msvcrt.printf().
Why?