在DAG中使用“depends_on_past”、“wait_for_downstream”和“priority_weight”参数来设置Airflow任务的调度顺序。例如：

from airflow import DAG
from airflow.operators.bash_operator import BashOperator
from datetime import timedelta

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': datetime(2021, 1, 1),
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 1,
    'retry_delay': timedelta(minutes=1),
    'wait_for_downstream': True,
    'priority_weight': 5
}

dag = DAG(
    'example_dag',
    default_args=default_args,
    description='Example DAG',
    schedule_interval=timedelta(days=1),
)

task_1 = BashOperator(
    task_id='task_1',
    bash_command='echo 1',
    dag=dag,
)

task_2 = BashOperator(
    task_id='task_2',
    bash_command='echo 2',
    dag=dag,
    priority_weight=10,
)

task_3 = BashOperator(
    task_id='task_3',
    bash_command='echo 3',
    dag=dag,
    depends_on_past=True,
)

task_1 >> task_2 >> task_3

在此示例中，task_1在task_2之前运行，而task_3依赖于task_2和task_1的成功运行结果。task_2的优先级较高，优先调度和运行。