code: def _dominant_task_for_jobs(tasks):
    
  
    per_job = _group_tasks_by_jobid(tasks)
  
    ret = []
    for job_id in per_job.keys():
      tasks_in_salience_order = sorted(per_job[job_id], key=_importance_of_task)
      ret.append(tasks_in_salience_order[0])
    return ret
docs: A list with, for each job, its dominant task.
  
    The dominant task is the one that exemplifies its job's
    status. It is either:
    - the first (FAILURE or CANCELED) task, or if none
    - the first RUNNING task, or if none
    - the first SUCCESS task.
  
    Args:
      tasks: a list of tasks to consider
  
    Returns:
      A list with, for each job, its dominant task.