Play Hand

#
# Problem #4: Playing a hand
#
def play_hand(hand, word_list):

    display_hand(hand)
    word = str(raw_input("Enter a word or . to finish"))
    score=0
    if word == ".":
        return score
    validity = is_valid_word(word,hand,word_list)

    if validity == False:

        print "choose another word"
        score += play_hand(hand,word_list)

    if validity == True:
        word_score = get_word_score(word,HAND_SIZE)
        print "word score",word_score
        score = score + word_score
        print "score",score
        score += play_hand((update_hand(hand,word)),word_list)
    return score