### Discussed in https://github.com/apache/airflow/discussions/33345

<div type='discussions-op-text'>

<sup>Originally posted by **vuphamcs** August 11, 2023</sup>
### Description

Is there a variable similar to `prev_start_date_success` but for the previous DAG run’s completion date? The value I’m hoping to retrieve to use within the next DAG run is `2023-08-10 16:04:30`

![image](https://github.com/apache/airflow/assets/1600760/9e2af349-4c3e-47e1-8a1a-9d8827b56f57)


### Use case/motivation

One particular use case is to help guarantee that the next DAG run only queries data that was inserted during the existing DAG run, and not the past DAG run.

```python
prev_ts = context['prev_end_date_success']

sql = f"SELECT * FROM results WHERE created_at > {context['prev_end_date_success']}"
```

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)
</div>
"""
        Copy common attributes from the given task.
        :param task: The task object to copy from
        :param pool_override: Use the pool_override instead of task's pool
        """
        _refresh_from_task(task_instance=self, task=task, pool_override=pool_override)
    @provide_session
    def clear_xcom_data(self, session: Session = NEW_SESSION) -> None:
        """Clear all XCom data from the database for the task instance.
        If the task is unmapped, all XComs matching this task ID in the same DAG
        run are removed. If the task is mapped, only the one with matching map
        index is removed.
        :param session: SQLAlchemy ORM Session
        """
        self.log.debug("Clearing XCom data")
        if self.map_index < 0:
            map_index: int | None = None
        else:
            map_index = self.map_index
        XCom.clear(
            dag_id=self.dag_id,
            task_id=self.task_id,
            run_id=self.run_id,
            map_index=map_index,
            session=session,
        )
    @property
    def key(self) -> TaskInstanceKey: