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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 cache_subnet_group_absent(name, region=None, key=None, keyid=None, profile=None, **args):
    '''
    Ensure a given cache subnet group is deleted.

    name
        Name of the cache subnet group.

    CacheSubnetGroupName
        A name for the cache subnet group.
        Note:  In general this parameter is not needed, as 'name' is used if it's not provided.

    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': {}}
    args = dict([(k, v) for k, v in args.items() if not k.startswith('_')])
    exists = __salt__['boto3_elasticache.'
                      'cache_subnet_group_exists'](name, region=region, key=key,
                                                  keyid=keyid, profile=profile)
    if exists:
        if __opts__['test']:
            ret['comment'] = 'Cache subnet group {0} would be removed.'.format(name)
            ret['result'] = None
            return ret
        deleted = __salt__['boto3_elasticache.'
                           'delete_cache_subnet_group'](name, region=region, key=key,
                                                       keyid=keyid, profile=profile, **args)
        if deleted:
            ret['changes']['old'] = name
            ret['changes']['new'] = None
        else:
            ret['result'] = False
            ret['comment'] = 'Failed to delete {0} cache_subnet group.'.format(name)
    else:
        ret['comment'] = 'Cache subnet group {0} already absent.'.format(name)
    return ret