시저 암호

list = 'abcdefghijklmnopqrstuvwxyz'

big_list = 'ABCDEFGHIZKLMNOPQRSTUVWXYZ'

print(list.index('z'))

def solution(s,n):

    answer = ''

    for i in s:

        if i.islower():

            answer += list[(list.index(i)+n)%26]

        elif i.isupper():

            answer += list[(list.index(i.lower())+n)%26].upper()

        else:

            answer += ' '

       

    return answer

print(solution('a B z',4))