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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 absent(name, region=None, key=None, keyid=None, profile=None):
    '''
    Ensure a pipeline with the service_name does not exist

    name
        Name of the service to ensure a data pipeline does not exist for.

    region
        Region to connect to.

    key
        Secret key to be used.

    keyid
        Access key to be used.

    profile
        A dict with region, key and keyid, or a pillar key (string)
        that contains a dict with region, key and keyid.
    '''
    ret = {'name': name, 'result': True, 'comment': '', 'changes': {}}

    result_pipeline_id = __salt__['boto_datapipeline.pipeline_id_from_name'](
        name,
        region=region,
        key=key,
        keyid=keyid,
        profile=profile,
    )
    if 'error' not in result_pipeline_id:
        pipeline_id = result_pipeline_id['result']
        if __opts__['test']:
            ret['comment'] = 'Data pipeline {0} set to be deleted.'.format(name)
            ret['result'] = None
            return ret
        else:
            __salt__['boto_datapipeline.delete_pipeline'](
                pipeline_id,
                region=region,
                key=key,
                keyid=keyid,
                profile=profile,
            )
            ret['changes']['old'] = {'pipeline_id': pipeline_id}
            ret['changes']['new'] = None
    else:
        ret['comment'] = 'AWS data pipeline {0} absent.'.format(name)

    return ret