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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, auth=None):
    '''
    Ensure a subnet does not exists

    name
        Name of the subnet

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

    __salt__['neutronng.setup_clouds'](auth)

    subnet = __salt__['neutronng.subnet_get'](name=name)

    if subnet:
        if __opts__['test'] is True:
            ret['result'] = None
            ret['changes'] = {'id': subnet.id}
            ret['comment'] = 'Project will be deleted.'
            return ret

        __salt__['neutronng.subnet_delete'](name=subnet)
        ret['changes']['id'] = name
        ret['comment'] = 'Deleted subnet'

    return ret