Airflow:如何从PostgreOperator推送XCOM值？

from airflow import DAG
from airflow.operators.postgres_operator import PostgresOperator
from datetime import datetime

default_args = {
    'start_date': datetime(2022, 1, 1)
}

with DAG('example_dag', default_args=default_args, schedule_interval='@daily') as dag:
    
    # Task 1: 执行PostgreSQL查询，并将结果推送到XCOM
    task1 = PostgresOperator(
        task_id='execute_query',
        sql='SELECT column FROM table',
        provide_context=True,
        dag=dag
    )
    
    # Task 2: 接收XCOM值，并进行处理
    def process_xcom_value(**context):
        xcom_value = context['ti'].xcom_pull(task_ids='execute_query')
        # 处理XCOM值的逻辑
        print(xcom_value)
    
    task2 = PythonOperator(
        task_id='process_xcom',
        python_callable=process_xcom_value,
        provide_context=True,
        dag=dag
    )
    
    task1 >> task2