How to keep only the noun words in a wordlist? python NLTK

Question

I have a wordlist, which consists many subjects. The subjects were auto extracted from sentences. I would like to keep only the noun from the subjects. As u can see some of the subjects have adj which i want to delete it.

wordlist=['country','all','middle','various drinks','few people','its reputation','German Embassy','many elections']
returnlist=[]
for word in wordlist:
    x=wn.synsets(word)
    for syn in x:
        if syn.pos() == 'n':
            returnlist.append(word)
            break
print returnlist

the results of above is :

['country','it',  'middle']

However, I want to get the result should be look like this

   wordlist=['country','it', 'middle','drinks','people','reputation','German Embassy','elections']

How to do that?

Answer 1

First your list is a result of not well tokenized text so i tokenized them again then search pos of all words to find nouns which pos contains NN :

>>> text=' '.join(wordlist).lower()
>>> tokens = nltk.word_tokenize(text)
>>> tags = nltk.pos_tag(tokens)
>>> nouns = [word for word,pos in tags if (pos == 'NN' or pos == 'NNP' or pos == 'NNS' or pos == 'NNPS')
]
>>> nouns
['country', 'drinks', 'people', 'Embassy', 'elections']