class Person:
    counter=0
    domain_name=""
    def __init__(self,first_name,last_name,age):
        self.__first_name = first_name
        self.__last_name = last_name
        self.__age = age
        Person.counter=Person.counter+1
        
    def __str__(self):
        return(self.__first_name + " "+ self.__last_name+ " is " + self.__age + " years old and her email id is "+self.__first_name+"."+self.__last_name+"@"+self.domain_name )
    def fullname(self):
        return(self.__first_name + " " + self.__last_name)
	
    @property
    def age(self):  
        return self.__age 
     # a setter function 
    @age.setter 
    def age(self, a): 
        self.__age = a