python 2.6.5 中的一个疑似bug

貌似设置了对象的__getattr__方法后，再使用hasattr检查是否存在某某属性时始终返回true

环境

os : ubuntu 10.4
python : 2.6.5

#!/usr/bin/python
# -*- coding:utf-8 -*-
import sys

class Person:
    #__userName = None
    __age = None
    aa = 1
    def __init__(self, name):
        self.__userName = name
    def __str__(self):
        if self.__userName is None:
            return ""
        else:
            return self.__userName

    __repr__ = __str__

    def getAge(self):
        return self.__age

    def setAge(self, value):
        self.__age = value

    def __getattr__(self, name):
        if name == 'sex':
            return self.__sex
        else:
            return ''

person = Person("jim")
bTemp = hasattr(person, "test")
print bTemp
if not bTemp:
    print "person.test is not exists!"
else:
    print "person.test exist!"

True
person.test exist!

#!/usr/bin/python
# -*- coding:utf-8 -*-
import sys

class Person:
    #__userName = None
    __age = None
    aa = 1
    def __init__(self, name):
        self.__userName = name
    def __str__(self):
        if self.__userName is None:
            return ""
        else:
            return self.__userName

    __repr__ = __str__

    def getAge(self):
        return self.__age

    def setAge(self, value):
        self.__age = value

    def __getattribute__(self, name): #将__getattr__换成__getattribute__
        if name == 'sex':
            return self.__sex
        else:
            return ''

person = Person("jim")
bTemp = hasattr(person, "test")
print bTemp
if not bTemp:
    print "person.test is not exists!"
else:
    print "person.test exist!"

False
person.sex is not exists!