human
Here's a good function header given the following:
I wrote the below code

    log.debug('Refreshing    buckets    cache    file')
    (key, keyid, service_url, verify_ssl, kms_keyid, location, path_style, https_enable) = _get_s3_key()
    metadata = {}
    def __get_s3_meta(bucket, key=key, keyid=keyid):
        (ret, marker) = ([], '')
        while True:
            tmp = __utils__['s3.query'](key=key, keyid=keyid, kms_keyid=keyid, bucket=bucket, service_url=service_url, verify_ssl=verify_ssl, location=location, return_bin=False, path_style=path_style, https_enable=https_enable, params={'marker': marker})
            headers = []
            for header in tmp:
                if ('Key' in header):
                    break
                headers.append(header)
            ret.extend(tmp)
            if all([(header.get('IsTruncated', 'false') == 'false') for header in headers]):
                break
            marker = tmp[(-1)]['Key']
        return ret
    if _is_env_per_bucket():
        for (saltenv, buckets) in six.iteritems(_get_buckets()):
            bucket_files = {}
            for bucket_name in buckets:
                s3_meta = __get_s3_meta(bucket_name)
                if (not s3_meta):
                    continue
                bucket_files[bucket_name] = [k for k in s3_meta if ('Key' in k)]
                if (len(bucket_files[bucket_name]) == 0):
                    meta_response = {}
                    for k in s3_meta:
                        if (('Code' in k) or ('Message' in k)):
                            meta_response.update(k)
                    try:
                        log.warning("'{0}'    response    for    bucket    '{1}'".format(meta_response['Message'], bucket_name))
                        continue
                    except KeyError:
                        if ('Code' in meta_response):
                            log.warning("'{0}'    response    for    bucket    '{1}'".format(meta_response['Code'], bucket_name))
                            continue
                        else:
                            log.warning('S3    Error!   ...

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

def _refresh_buckets_cache_file(cache_file):