これはあなたの質問に直接答えるものではありませんが、ここで遭遇した問題のいくつかを理解するのに役立つかもしれません. ほとんどの場合、リストに追加する方法を確認できます。できれば、文字列、リスト、および整数の長さの取得の違いを確認できます (これは実際にはできません!)。
以下のコードを実行して、何が起こっているかを調べてください。
def step_forward():
    raw_input('(Press ENTER to continue...)')
    print('\n.\n.\n.')
def experiment():
    """ Run a whole lot experiments to explore the idea of lists and
variables"""
    # create an empty list, test length
    word_list = []
    print('the length of word_list is:  {}'.format(len(word_list)))
    # expect output to be zero
    step_forward()
    # add some words to the list
    print('\nAdding some words...')
    word_list.append('Hello')
    word_list.append('Experimentation')
    word_list.append('Interesting')
    word_list.append('ending')
    # test length of word_list again
    print('\ttesting length again...')
    print('\tthe length of word_list is:  {}'.format(len(word_list)))
    step_forward()
    # print the length of each word in the list
    print('\nget the length of each word...')
    for each_word in word_list:
        print('\t{word} has a length of:  {length}'.format(word=each_word, length=len(each_word)))
        # output:
        #    Hello has a length of:  5
        #    Experimentation has a length of:  15
        #    Interesting has a length of:  11
        #    ending has a length of:  6
    step_forward()
    # set up a couple of counters
    short_word = 0
    long_word = 0
    # test the length of the counters:
    print('\nTrying to get the length of our counter variables...')
    try:
        len(short_word)
        len(long_word)
    except TypeError:
        print('\tERROR:  You can not get the length of an int')
    # you see, you can't get the length of an int
    # but, you can get the length of a word, or string!
    step_forward()
    # we will make some new tests, and some assumptions:
    #     short_word:    a word is short, if it has less than 9 letters
    #     long_word:     a word is long, if it has 9 or more letters
    # this test will count how many short and long words there are
    print('\nHow many short and long words are there?...')
    for each_word in word_list:
        if len(each_word) < 9:
            short_word += 1
        else:
            long_word += 1
    print('\tThere are {short} short words and {long} long words.'.format(short=short_word, long=long_word))
    step_forward()
    # BUT... what if we want to know which are the SHORT words and which are the LONG words?
    short_word = 0
    long_word = 0
    for each_word in word_list:
        if len(each_word) < 9:
            short_word += 1
            print('\t{word} is a SHORT word'.format(word=each_word))
        else:
            long_word += 1
            print('\t{word} is a LONG word'.format(word=each_word))
    step_forward()
    # and lastly, if you need to use the short of long words again, you can
    # create new sublists
    print('\nMaking two new lists...')
    shorts = []
    longs = []
    short_word = 0
    long_word = 0
    for each_word in word_list:
        if len(each_word) < 9:
            short_word += 1
            shorts.append(each_word)
        else:
            long_word += 1
            longs.append(each_word)
    print('short list:  {}'.format(shorts))
    print('long list:  {}'.format(longs))
    # now, the counters short_words and long_words should equal the length of the new lists
    if short_word == len(shorts) and long_word == len(longs):
        print('Hurray, its works!')
    else:
        print('Oh no!')
experiment()
うまくいけば、ここで私たちの回答を見て、上記のミニ実験を調べると、コードで必要なことを実行できるようになるでしょう:)