문제 : https://programmers.co.kr/learn/courses/30/lessons/42888
def solution(record):
answer = []
situations = []
name = {}
for re in record: #1
situations.append(re.split())
for now in situations: #2
if now[0] != 'Leave':
name[now[1]] = now[2]
for text in situations: #3
if text[0] == 'Enter':
answer.append(f'{name[text[1]]}님이 들어왔습니다.')
elif text[0] == 'Leave':
answer.append(f'{name[text[1]]}님이 나갔습니다.')
return answer