code: func ToWriter(src string, w io.Writer, options Options) error {
  	u, err := url.Parse(src)
  	if err != nil {
  		return errors.Wrap(err, "invalid src URL")
  	}
  	return FromURL(u, w, options)
  }
docs: // ToWriter downloads the specified `src` URL to `w` writer using
  // the specified `Options`.