import pickle

class DVD:

    def __init__(self,tilte,year=None,duration=None,director_id=None):

        self.title=tilte

        self.year=year

        self.duration=duration

        self.director_id=director_id

        self.filename=self.title.replace(',','_')+'.pickle'

    def save(self,filename=None):

        with open(self.filename,'wb')as fh:

            pickle.dump(self,fh)

    @staticmethod

    def load(filename):

        with open(filename,'rb')as fh:

            return pickle.load(fh)

    def __str__(self):

        return repr(self)

    def __repr__(self):

        return "DVD('{0}',{1},{2},'{3}')".format(self.title,self.year,self.duration,self.director_id)

dvd1=DVD('Birds',2016,1,'Justin Lin')

dvd1.save()

dvd2=DVD.load('Birds.pickle')

print(dvd2)