code: func (o *httpOps) DownloadSignatureAgain(a *asc) (readSeekCloser, error) {
  	ensureLogger(o.Debug)
  	ascFile, retry, err := o.DownloadSignature(a)
  	if err != nil {
  		return nil, err
  	}
  	if retry {
  		return nil, fmt.Errorf("error downloading the signature file: server asked to defer the download again")
  	}
  	return ascFile, nil
  }
docs: // DownloadSignatureAgain does a similar thing to DownloadSignature,
  // but it expects the signature to be actually provided, that is - no
  // deferring this time.