문제 링크

정답 :

def solution(picture, k):
    answer = []
    
    for i in picture:
        newPicture = ''.join([x * k for x in i])
        for _ in range(k):
            answer.append(newPicture)
            
    return answer

방법 1:

def solution(picture, k):
    answer = []
    for i in range(len(picture)):
        for _ in range(k):
            answer.append(picture[i].replace('.', '.' * k).replace('x', 'x' * k))
    return answer