为什么这样不对
class Person(object):
def __init__(self, name, score):
self.__score=score
def get_grade(score):
if score>85:
return 'A'
elif score>60:
return 'B'
else:
return 'C'
p1 = Person('Bob', 90)
p2 = Person('Alice', 65)
p3 = Person('Tim', 48)
print p1.get_grade()
print p2.get_grade()
print p3.get_grade()
