Python failed to `import nltk` in my script but wo

I figured out the reason, I named the original script file nltk.py, so python tried to import word_tokenize from the script file orz. Sorry for this silly mistake.

I am trying to use nltk in Python on Windows. I have installed nltk and nltk data.

However, when I try to run python -u 'filename.py' in commandline, it gives an error as follows.

Traceback (most recent call last):
  File "filename.py", line 1, in (module)
    from nltk import word_tokenize
  File "filenmae.py", line 1, in (module)
    from nltk import word_tokenize
ImportError: cannot import name word_tokenize

On the other hand, when I run python < 'filename.py' the correct result is given.

The code in filename.py is a simple test code, as given below.

from nltk import word_tokenize
tokens = word_tokenize('hello i am your friend')
print(tokens)

Could you help me with this? Thanks in advance.

I tried re-installing nltk following the source installation instruction here. But it did not work.

Additionally, I had python 3.3 installed in the past, but I found that nltk cannot recognize python 3.3 during installation, so I installed python 2.7. And now there are actually two versions of python on my computer.

The related User Path is C:\Python27.

In System Path, the related fields are:

Path C:\Python27\

PYTHONIOENCODING utf-8

PYTHONPATH C:\Python27

The python version when I run it in command line is,

Python 2.7.3 (Date) [MSC v.1500 32 bit (Intel)] on win32

Also, I tried running the following code on both command line and using a script file given here：

import nltk
import sys
print(nltk)
print(sys.executable)

In the command line the results are

>>> print(nltk)
<module 'nltk' from 'C:\Python27\lib\site-packages\nltk\__init__.pyc'>
>>> print(sys.executable)
C:\Python27\python.exe

Using a script the results are

<module 'nltk' from 'C:\Users\username\Documents\nltk.py'>
C:\Python27\python.exe
<module 'nltk' from 'C:\Users\username\Documents\nltk.py'>
C:\Python27\python.exe

I figured out the reason, I named the original script file nltk.py, so python tried to import word_tokenize from the script file orz. Sorry for this silly mistake.