Return a list of the VMs that are on the provider. Only a list of VM names,
    and their state, is returned. This is the minimum amount of information
    needed to check for existing VMs.

def list_nodes_min(location=None, call=None):
    '''
    Return a list of the VMs that are on the provider. Only a list of VM names,
    and their state, is returned. This is the minimum amount of information
    needed to check for existing VMs.
    '''
    if call == 'action':
        raise SaltCloudSystemExit(
            'The list_nodes_min function must be called with -f or --function.'
        )

    ret = {}
    params = {'Action': 'DescribeInstances'}
    instances = aws.query(params,
                          location=get_location(),
                          provider=get_provider(),
                          opts=__opts__,
                          sigver='4')
    if 'error' in instances:
        raise SaltCloudSystemExit(
            'An error occurred while listing nodes: {0}'.format(
                instances['error']['Errors']['Error']['Message']
            )
        )

    for instance in instances:
        if isinstance(instance['instancesSet']['item'], list):
            items = instance['instancesSet']['item']
        else:
            items = [instance['instancesSet']['item']]

        for item in items:
            state = item['instanceState']['name']
            name = _extract_name_tag(item)
            id = item['instanceId']
            ret[name] = {'state': state, 'id': id}
    return ret