POS Tagging

[Hephzibah]

I just started working on POS tagging with these codes:

import nltk
text = nltk.word_tokenize("And now for something completely
different")
#print text
print nltk.pos_tag(text)

Python prompted me to download a resource with these codes:

Resource 'taggers/maxent_treebank_pos_tagger/english.pickle' not
found.  Please use the NLTK Downloader to obtain the resource:

I download the resources available using nltk.download(). But  I
couldn't run POS tagger. Python gave my the following message:

Traceback (most recent call last):
  File "C:/Python25/tag practices.py", line 5, in <module>
    print nltk.pos_tag(text)
  File "C:\Python25\lib\site-packages\nltk\tag\__init__.py", line 62,
in pos_tag
    tagger = nltk.data.load(_POS_TAGGER)
  File "C:\Python25\lib\site-packages\nltk\data.py", line 492, in load
    resource_val = pickle.load(_open(resource_url))
  File "C:\Python25\lib\site-packages\nltk\classify\maxent.py", line
57, in <module>
    import numpy
ImportError: No module named numpy

Can someone pls. tell me what I'm supposed to do next?

Thanks,
Hephzibah