Strange Errors in Python-Mode

I am using the python mode. When i try to evaluate the following def using C-M-x i get this error from the python interpreter which looks strange:

def foo(*args, **kwargs):
    print args, kwargs

>>> Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/amir/programming/python/tst.py", line 2
    if True:
           ^
IndentationError: expected an indented block

Can any one say why this happens? The file is only including the above function definition beginning from the first line an nothing more.