pickle实现实例化对象的存与读

import pickle
class Mypickle:
    def __init__(self,path):
        self.file = path
    def dump(self,obj):
        with open(self.file, 'ab') as f:
            pickle.dump(obj, f)
    def load(self):
        with open(self.file,'rb') as f:
            while True:
                try:
                    yield pickle.load(f)
                except EOFError:
                    break
a=A('cat',1)
s=Mypickle('file')
s.dump(a)
s.load()