title: How to Trigger a DAG on the success of a another DAG in Airflow using Python?
body: <p>I have a python DAG <code>Parent Job</code> and DAG <code>Child Job</code>. The tasks in the <code>Child Job</code> should be triggered on the successful completion of the <code>Parent Job</code> tasks which are run daily. How can add external job trigger ?</p>
  
  <p><strong>MY CODE</strong></p>
  
  <pre><code>from datetime import datetime, timedelta
  from airflow import DAG
  from airflow.operators.postgres_operator import PostgresOperator
  from utils import FAILURE_EMAILS
  
  yesterday = datetime.combine(datetime.today() - timedelta(1), datetime.min.time())
  
  
  default_args = {
      'owner': 'airflow',
      'depends_on_past': False,
      'start_date': yesterday,
      'email': FAILURE_EMAILS,
      'email_on_failure': False,
      'email_on_retry': False,
      'retries': 1,
      'retry_delay': timedelta(minutes=5)
  }
  
  dag = DAG('Child Job', default_args=default_args, schedule_interval='@daily')
  
  execute_notebook = PostgresOperator(
    task_id='data_sql',
    postgres_conn_id='REDSHIFT_CONN',
    sql="SELECT * FROM athena_rs.shipments limit 5",
    dag=dag
  )
  </code></pre>