### 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>
"""Base test class for TestPythonOperator and TestPythonSensor classes"""
    opcls: type[BaseOperator]
    dag_id: str
    task_id: str
    run_id: str
    dag: DAG
    ds_templated: str
    default_date: datetime = DEFAULT_DATE
    @pytest.fixture(autouse=True)
    def base_tests_setup(self, request, create_task_instance_of_operator, dag_maker):
        self.dag_id = f"dag_{slugify(request.cls.__name__)}"
        self.task_id = f"task_{slugify(request.node.name, max_length=40)}"
        self.run_id = f"run_{slugify(request.node.name, max_length=40)}"
        self.ds_templated = self.default_date.date().isoformat()
        self.ti_maker = create_task_instance_of_operator
        self.dag_maker = dag_maker
        self.dag = self.dag_maker(self.dag_id, template_searchpath=TEMPLATE_SEARCHPATH).dag
        clear_db_runs()
        yield
        clear_db_runs()
    @staticmethod
    def assert_expected_task_states(dag_run: DagRun, expected_states: dict):