Wordnet add synsets

from nltk.corpus import wordnet as wn
from collections import defaultdict
from nltk.corpus.reader.wordnet import Synset
import cPickle as pickle

def synset2pos(x):
    return str(x.offset)+'-'+x.pos

try:
    wordnet = pickle.load(open('wn.pk','rb'))
except:
    wordnet = defaultdict(dict)
    for i in wn.all_synsets():
        offset= synset2pos(i)
        hyper = [synset2pos(j) for j in i.hypernyms()]
        hypo = [synset2pos(j) for j in i.hyponyms()]

        wordnet[offset] = {'hypers':hyper,'hypos':hypo, 'lemmas':i.lemma_names}

    with open('wn.pk','wb') as fout:
        pickle.dump(wordnet,fout)

wordnet['99999999-n'] = {'hypers':['12345678-n','23456789-n'],
                                                 'hypos':['98765432-n','87654321-n'],
                                                 'lemmas': ['foobar','barfoo']}

wordnet['98765432-n'] = {'hypers':['99999999-n','23456789-n'],
                                                 'hypos':['87654321-n'],
                                                 'lemmas': ['barbar']}

wordnet['87654321-n'] = {'hypers':['98765432-n','23456789-n'],
                                                 'hypos':[],
                                                 'lemmas': ['blacksheep']}

# To access synsets with query words.
query = 'dog'
print [i for i in wordnet if query in wordnet[i]['lemmas']]
print