在python 3.4.0中导入nltk

Question

我是python的新手并使用python 3.4.0。我安装了nltk和six，但导入时出错。我也尝试过升级。它是最新的。

import nltk
     Traceback (most recent call last):
     File "<pyshell#1>", line 1, in <module>
     import nltk
     File "C:\Python34\lib\site-packages\nltk\__init__.py", line 128, in        <module>
    from nltk.chunk import *
    File "C:\Python34\lib\site-packages\nltk\chunk\__init__.py", line 157, in <module>
    from nltk.chunk.api import ChunkParserI
    File "C:\Python34\lib\site-packages\nltk\chunk\api.py", line 13, in <module>
    from nltk.parse import ParserI
    File "C:\Python34\lib\site-packages\nltk\parse\__init__.py", line 77, in <module>
    from nltk.parse.malt import MaltParser
    File "C:\Python34\lib\site-packages\nltk\parse\malt.py", line 14, in <module>
    from six import text_type
    ImportError: No module named 'six'