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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):
    '''
    Ensure that a network is absent.

    name
        Name of the network

    Usage Example:

    .. code-block:: yaml

        network_foo:
          docker_network.absent
    '''
    ret = {'name': name,
           'changes': {},
           'result': False,
           'comment': ''}

    try:
        network = __salt__['docker.inspect_network'](name)
    except CommandExecutionError as exc:
        msg = exc.__str__()
        if '404' in msg:
            # Network not present
            network = None
        else:
            ret['comment'] = msg
            return ret

    if network is None:
        ret['result'] = True
        ret['comment'] = 'Network \'{0}\' already absent'.format(name)
        return ret

    if __opts__['test']:
        ret['result'] = None
        ret['comment'] = 'Network \'{0}\' will be removed'.format(name)
        return ret

    return _remove_network(network)