code: def setup_method(self):
      args = {"owner": "airflow", "start_date": DEFAULT_DATE}
      dag = DAG(TEST_DAG_ID, default_args=args)
      self.dag = dag
  
file_path: airflow/tests/providers/postgres/operators/test_postgres.py
imports: from __future__ import annotations
  import pytest
  from airflow.models.dag import DAG
  from airflow.providers.postgres.hooks.postgres import PostgresHook
  from airflow.providers.postgres.operators.postgres import PostgresOperator
  from airflow.utils import timezone
label_desc: Use image node_id 1 for calling the TestPostgres obj's underlying member method code with example usage: obj.setup_method() without return types