Does on_failure_callback run exclusively on the task level and not on the level of the entire DAG?

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Onfailurecallback in Apache Airflow runs exclusively on the task level and not on the level of the entire DAG. It is triggered only when a particular task fails, and not when the entire DAG fails. The onfailurecallback function is declared in the DAG's defaultargs dictionary, and is executed only for the tasks that have it specified in their own defaultargs.