code: def persist(self):
          
          if self.object_hash:
              data = dill.dumps(self.object_property)
              f = ContentFile(data)
              self.object_file.save(self.object_hash, f, save=False)
              f.close()
              self._persisted = True
          return self._persisted
docs: a private method that persists an estimator object to the filesystem