def METHOD_NAME(self):
    """Loads existing timestamps from db"""
    def _deserialize():
        try:
            info = manage.NetboxInfo.objects.get(
                netbox__id=self._get_netbox().id,
                key=INFO_KEY_NAME,
                variable=self.var_name,
            )
        except manage.NetboxInfo.DoesNotExist:
            return None
        try:
            return json.loads(info.value)
        except Exception:
            return None
    self.loaded_times = yield db.run_in_thread(_deserialize)
    defer.returnValue(self.loaded_times)