python单例模式

#coding:utf-8
#单例模式
class Single(object):
    _instans = None
    _isTrue = False
    
    def __new__(cls,name,age):
        if (cls._instans==None):
            cls._instans = object.__new__(cls)
        return cls._instans
    def __init__(self,name,age):
        if(self._isTrue ==False):
            print('-----------')
            self.name = name
            self.age = age
            self._isTrue = True
a = Single('xiaoa',5)
print('姓名：%s，年龄：%d,'%(a.name,a.age))
b = Single('xiaow',6)
print('姓名：%s，年龄：%d,'%(b.name,b.age))