# -*- coding: utf-8 -*-
#
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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
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#   http://www.apache.org/licenses/LICENSE-2.0
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from airflow.exceptions import DagNotFound, TaskNotFound
from airflow.models import DagBag


def get_task(dag_id, task_id):
    """Return the task object identified by the given dag_id and task_id."""
    dagbag = DagBag()

    # Check DAG exists.
    if dag_id not in dagbag.dags:
        error_message = "Dag id {} not found".format(dag_id)
        raise DagNotFound(error_message)

    # Get DAG object and check Task Exists
    dag = dagbag.get_dag(dag_id)
    if not dag.has_task(task_id):
        error_message = 'Task {} not found in dag {}'.format(task_id, dag_id)
        raise TaskNotFound(error_message)

    # Return the task.
    return dag.get_task(task_id)
