def get_tasks_at_level(workflow, level):

    """
    return the tasks at given level

    Args:
        workflow (DAG): DAG object of workflow
        level (int): level which output tasks needed to be

    Returns:
        list(Node)
    """
    tasks = []
    for task in workflow.get_nodes():
        if workflow.get_nodes()[task].get_level() == level:
            tasks.append(workflow.get_nodes()[task])
    return tasks