def all_squares_filled():
    """ Returns True iff all squares have been filled. """
    for row in range(1, 4):     # range(1, 4) returns the list [1, 2, 3]
        if EMPTY in get_row(row):
            return False    # this row contains an empty square, we know enough
    return True     # no empty squares found, all squares are filled
 Returns True iff all squares have been filled. 
recipes/Python/576661_TicTacToe/recipe-576661.py