카카오 오픈채팅방

def solution(records):
    users = {}
    cmd = {"Enter": "님이 들어왔습니다.", "Leave": "님이 나갔습니다."}
    for record in records:
        strSplit = record.split()
        if strSplit[0] == 'Enter':
            users[strSplit[1]] = strSplit[2]
        elif strSplit[0] == 'Change':
            users[strSplit[1]] = strSplit[2]

    output = []
    for record in records:
        strSplit = record.split()
        if strSplit[0] != "Change":
            output.append('{}{}'.format(users[strSplit[1]], cmd[strSplit[0]]))

    return output