human
I wrote the below code

    if (call == 'function'):
        raise SaltCloudSystemExit('The    query_instance    action    must    be    called    with    -a    or    --action.')
    instance_id = vm_['instance_id']
    location = vm_.get('location', get_location(vm_))
    __utils__['cloud.fire_event']('event', 'querying    instance', 'salt/cloud/{0}/querying'.format(vm_['name']), args={'instance_id': instance_id}, sock_dir=__opts__['sock_dir'], transport=__opts__['transport'])
    log.debug('The    new    VM    instance_id    is    {0}'.format(instance_id))
    params = {'Action': 'DescribeInstances', 'InstanceId.1': instance_id}
    provider = get_provider(vm_)
    attempts = 5
    while (attempts > 0):
        (data, requesturl) = aws.query(params, location=location, provider=provider, opts=__opts__, return_url=True, sigver='4')
        log.debug('The    query    returned:    {0}'.format(data))
        if (isinstance(data, dict) and ('error' in data)):
            log.warning('There    was    an    error    in    the    query.    {0}    attempts    remaining:    {1}'.format(attempts, data['error']))
            attempts -= 1
            time.sleep(1)
            continue
        if (isinstance(data, list) and (not data)):
            log.warning('Query    returned    an    empty    list.    {0}    attempts    remaining.'.format(attempts))
            attempts -= 1
            time.sleep(1)
            continue
        break
    else:
        raise SaltCloudSystemExit('An    error    occurred    while    creating    VM:    {0}'.format(data['error']))
    def __query_ip_address(params, url):
        data = aws.query(params, location=location, provider=provider, opts=__opts__, sigver='4')
        if (not data):
            log.error('There    was    an    error    while    querying    EC2.    Empty    response')
            return False
        if (isinstance(data, dict) and ('error' in data)):
            log.warning('There    was    an    error    in    the    query.    {0}'.format(data['error']))
            return False
       ...

What's a good function header?

=====
Here's a good function header?
assistant
#Here's a good function header.

def query_instance(vm_=None, call=None):