NLTK and Stopwords Fail #lookuperror

I am trying to start a project of sentiment analysis and I will use the stop words method. I made some research and I found that nltk have stopwords but when I execute the command there is an error.

What I do is the following, in order to know which are the words that nltk use (like what you may found here http://www.nltk.org/book/ch02.html in section4.1):

    from nltk.corpus import stopwords
    stopwords.words('english')

But when I press enter I obtain

    ---------------------------------------------------------------------------
    LookupError                               Traceback (most recent call last)
    <ipython-input-6-ff9cd17f22b2> in <module>()
    ----> 1 stopwords.words('english')

    C:\Users\Usuario\Anaconda\lib\site-packages\nltk\corpus\util.pyc in __getattr__(self, attr)
     66
     67     def __getattr__(self, attr):
    ---> 68         self.__load()
     69         # This looks circular, but its not, since __load() changes our
     70         # __class__ to something new:

    C:\Users\Usuario\Anaconda\lib\site-packages\nltk\corpus\util.pyc in __load(self)
     54             except LookupError, e:
     55                 try: root = nltk.data.find('corpora/%s' % zip_name)
    ---> 56                 except LookupError: raise e
     57
     58         # Load the corpus.

    LookupError:
    **********************************************************************
      Resource 'corpora/stopwords' not found.  Please use the NLTK
      Downloader to obtain the resource:  >>> nltk.download()
      Searched in:
    - 'C:\\Users\\Meru/nltk_data'
    - 'C:\\nltk_data'
    - 'D:\\nltk_data'
    - 'E:\\nltk_data'
    - 'C:\\Users\\Meru\\Anaconda\\nltk_data'
    - 'C:\\Users\\Meru\\Anaconda\\lib\\nltk_data'
    - 'C:\\Users\\Meru\\AppData\\Roaming\\nltk_data'
    **********************************************************************

And, because of this problem things like this cannot run properly (obtaining the same error):

    >>> from nltk.corpus import stopwords
    >>> stop = stopwords.words('english')
    >>> sentence = "this is a foo bar sentence"
    >>> print [i for i in sentence.split() if i not in stop]

Do you know what may be problem? I must use words in Spanish, do you recomend another method? I also thought using Goslate package with datasets in english

Thanks for reading!

P.D.: I use Ananconda

You don't seem to have the stopwords corpus on your computer.

You need to start the NLTK Downloader and download all the data you need.

Open a Python console and do the following:

    >>> import nltk
    >>> nltk.download()
    showing info http://nltk.github.com/nltk_data/

In the GUI window that opens simply press the 'Download' button to download all corpora or go to the 'Corpora' tab and only download the ones you need/want.

From: stackoverflow.com/q/26693736