类示例

class Cat(object):
	__name = ''
	__age =0
	def __init__(self,name,age):
		self.__name = name
		self.__age = age
		print 'init cat , name is %s;age is %d' %(name,age)
	def getName(self):
		return self.__name
	def getAge(self):
		return self.__age
	def setName(self,name):
		self.__name = name
	def setAge(self,age):
		self.__age = age
	
	#bool(self) is True if you have not overwrite this function
	def __nonzero__(self):
		'return true if name is null'
		if __name=='' :
			return True
		return False
print  'Hello .'