def find_used_word(self, url):
words = {}
for word in split_words(url):
if exists_used_word_in_db(word):
words.setdefault(word,
get_last_modified_in_db(word))
oldest_word = ""
if bool(words):
oldest_word = min(words)
else:
oldest_word = choose_last_modified_used_word_in_db()
return select_used_word_in_db(oldest_word, url)
def find_url(self, word):
if exists_used_word_in_db(word):
return get_url_in_db(word)
return None
