code: func (lo *largeObject) md5Content(r io.ReadSeeker) (string, string, error) {
  	// #nosec G401
  	h := md5.New()
  	mw := io.MultiWriter(h, lo.md5)
  	if _, err := io.Copy(mw, r); err != nil {
  		return "", "", err
  	}
  	sum := h.Sum(nil)
  	hexSum := fmt.Sprintf("%x", sum)
  	// add to checksum of all parts for verification on upload completion
  	if _, err := lo.md5OfParts.Write(sum); err != nil {
  		return "", "", err
  	}
  	return base64.StdEncoding.EncodeToString(sum), hexSum, nil
  }
docs: // Md5 functions