@property为什么只能在return私有属性时生效？求大神解答
class Student(object):
def __init__(self, name, score):
self.name = name
self.__score = score
@property
def score(self):
return self.__score
@score.setter
def score(self, score):
if score < 0 or score > 100:
raise ValueError('invalid score')
self.__score = score
@property
def grade(self):
if self.__score > 80 or self.__score == 80:
self.__grade='A'
elif self.__score < 60:
self.__grade='C'
else:
self.__grade='B'
return self.__grade
s = Student('Bob', 59)
print s.grade
s.score = 60
print s.grade
s.score = 99
print s.grade如果我把s.__grade 改成s.grade 就打印不出了，这是为什呢？
