def get_iter_cb(self, key, value, it, org_key, include_key=False):
        _log.analyze(self.node.id, "+ BEGIN", {'value': value, 'key': org_key})
        if value:
            value = self.coder.decode(value)
            it.append((key, value) if include_key else value)
            _log.analyze(self.node.id, "+", {'value': value, 'key': org_key})
        else:
            _log.analyze(self.node.id, "+", {'value': 'FailedElement', 'key': org_key})
            it.append((key, dynops.FailedElement) if include_key else dynops.FailedElement)
get callback
dataset/ETHPy150Open EricssonResearch/calvin-base/calvin/runtime/north/storage.py/Storage.get_iter_cb