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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_action(task):
 """Determine if a task is an action task. Trusted decision and action tasks are important in that they can generate other valid tasks. The verification of decision and action tasks is slightly different, so we need to be able to tell them apart. This checks for the following things:: * ``task.payload.env.ACTION_CALLBACK`` exists * ``task.extra.action`` exists Args: task (dict):
 the task definition to check Returns: bool: True if it's an action """

    result = False
    if _extract_from_env_in_payload(task, 'ACTION_CALLBACK'):
        result = True
    if task.get('extra', {}).get('action') is not None:
        result = True
    return result