NPR Puzzle: Trees to Herbs and Spices in Python

from nltk.corpus import wordnet as wn

def get_category_members(name):
    '''
    Use NLTK to get members of a category

    Huge thanks to http://stackoverflow.com/questions/15330725/how-to-get-all-the-hyponyms-of-a-word-synset-in-python-nltk-and-wordnet
    '''
    members = set()
    synsets = wn.synsets(name)
    for synset in synsets:
        members = members.union(set([w for s in synset.closure(lambda s:s.hyponyms(),depth=10) for w in s.lemma_names]))
    return members

def w1_in_w2(w1,w2):
    '''
    Return leftover letters if all the letters from w1 are in w2
    Return False otherwise
    '''
    for c in w1:
        if c not in w2:
            return False
        else:
            pos = w2.find(c)
            w2 = w2[:pos] + w2[pos+1:]
    return w2


# Set of trees
trees = frozenset(get_category_members('tree'))

# Set of herbs and spices
herbs_spices = set()
for x in ('herb','spice'):
    herbs_spices = herbs_spices.union(get_category_members(x))
# Dictionary to help find anagrams
sorted_to_word = dict()
for word in herbs_spices:
    word = word.lower()
    s = ''.join(sorted(word))
    try:
        sorted_to_word[s].append(word)
    except KeyError:
        sorted_to_word[s] = [word]

# Go through and give results
for tree in trees:
    for herb in herbs_spices:
        leftover = w1_in_w2(herb.lower(),tree.lower())
        if leftover:
            l = leftover.replace('_','')
            s = ''.join(sorted(l))
            try:
                new_words = sorted_to_word[s]
            except KeyError:
                new_words = []
            for spice in new_words:
                print "%s -> %s %s" % (tree, herb, spice)