Por que a importação de ctypes levantar ImportError?

Question

Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)] on
win32
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>>> import ctypes
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python26\lib\ctypes\__init__.py", line 17, in <module>
    from struct import calcsize as _calcsize
ImportError: cannot import name calcsize

>>> from ctypes import *
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python26\lib\ctypes\__init__.py", line 17, in <module>
    from struct import calcsize as _calcsize
ImportError: cannot import name calcsize
>>>

Answer 1

Parece que você tem uma outra struct.py em sua em algum lugar do caminho.

Tente isto para ver onde python encontra seu módulo struct:

>>> import inspect
>>> import struct
>>> inspect.getabsfile(struct)
'c:\\python26\\lib\\struct.py'