ImportError: No module named jaraco.itertools in Python

[manhnt]

I'm converting a .py file to a .exe file. It is on the 'dist' folder(using py2exe). It complies and runs normally in Python shell. But in an executable file, it couldn't run with this traceback:

Error:
Traceback (most recent call last):
  File "VAssistant.py", line 5, in <module>
  File "wolframalpha\__init__.pyc", line 7, in <module>
ImportError: No module named jaraco.itertools

File .py includes WolframAlpha(I'm using Python version 2.7)