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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, driver=None):
    '''
    Ensure that a volume is absent.

    .. versionadded:: 2015.8.4
    .. versionchanged:: 2017.7.0
        This state was renamed from **docker.volume_absent** to **docker_volume.absent**

    name
        Name of the volume

    Usage Examples:

    .. code-block:: yaml

        volume_foo:
          docker_volume.absent

    '''
    ret = {'name': name,
           'changes': {},
           'result': False,
           'comment': ''}

    volume = _find_volume(name)
    if not volume:
        ret['result'] = True
        ret['comment'] = 'Volume \'{0}\' already absent'.format(name)
        return ret

    try:
        ret['changes']['removed'] = __salt__['docker.remove_volume'](name)
        ret['result'] = True
    except Exception as exc:
        ret['comment'] = ('Failed to remove volume \'{0}\': {1}'
                          .format(name, exc))
    return ret