[Programmers] 대문자와 소문자

https://school.programmers.co.kr/learn/courses/30/lessons/120893

프로그래머스

 

def solution(my_string):
    answer = ''
    for i in my_string :
        if i.isupper() :
            answer += i.lower()
        else :
            answer += i.upper()
    return answer