A class for looking up words

trie.py

from collections import defaultdict

def trie():
    return defaultdict(trie)

class Trie(object):
    TERMINATOR = "<END>"
    def __init__(self):
        self.t = trie()
    def insert_word(self, word):
        t = self.t
        for c in word:
            t = t[c]
        t[self.TERMINATOR]
    def lookup_word(self, word):
        t = self.t
        for c in word:
            if c in t:
                t = t[c]
            else:
                return False
        return self.TERMINATOR in t