def METHOD_NAME(payload, expiry, file_extension, mimetype=None,
                           content_disposition=None, download_id=None,
                           extras=None, owner_ids=None):
    """
    Expose a cache download object.
    """
    ref = CachedDownload.create(payload, expiry, mimetype=mimetype,
                                content_disposition=content_disposition,
                                download_id=download_id, extras=extras,
                                suffix=file_extension, owner_ids=owner_ids)
    ref.save(expiry)
    return ref