'Tests that the python callable is invoked on task run.'

def test_python_operator_run(self):

    task = PythonOperator(python_callable=self.do_run, task_id=u'python_operator', dag=self.dag)
    self.assertFalse(self.is_run())
    task.run(start_date=DEFAULT_DATE, end_date=DEFAULT_DATE)
    self.assertTrue(self.is_run())
