密码验证合格程序

def solve(pwd):
    if len(pwd) <= 8:
        print('NG')
        return
    has_upper = has_lower = has_digit = has_other = False
    for c in pwd:
        if c.isupper(): has_upper = True
        elif c.islower(): has_lower = True
        elif c.isdigit(): has_digit = True
        else: has_other = True
    if sum([has_upper, has_lower, has_digit, has_other]) < 3:
        print('NG')
        return
    for i in range(len(pwd) - 2):
        if pwd[i:i+3] in pwd[i+3:]:
            print('NG')
            return
    print('OK')