Сортировка вводимых данных пузырьковым методом

if __name__ == "__main__":
    arr = []
    while True:
        s = raw_input()
        if not s or s == "":
            break
        arr.append(s.lower())

    i = len(arr)
    while i > 1:
       for j in xrange(i - 1):
           if arr[j] > arr[j + 1]:
               arr[j+1], arr[j] = arr[j], arr[j+1]
       i -= 1

    for a in arr:
        print(a)