class 의 목록 유도 식 오류

잘못 을 보고 하 다
코드

class B:
    b = 'b'
    ls = [b + i for i in '123']

오류 알림

Traceback (most recent call last):
  File "C:/Users/hongjiwei/PycharmProjects/small_draft/z.py", line 12, in <module>
    class B:
  File "C:/Users/hongjiwei/PycharmProjects/small_draft/z.py", line 14, in B
    ls = [b + i for i in '123']
  File "C:/Users/hongjiwei/PycharmProjects/small_draft/z.py", line 14, in <listcomp>
    ls = [b + i for i in '123']
NameError: name 'b' is not defined

해결 방법

class A:
    a = 'a'
    ls = []
    for i in '123':
        ls.append(a + i)

print(' '.join(A.ls))

print
a1 a2 a3