code: func DecodeString(s string) ([]byte, error) {
  	src := []byte(s)
  	dst := make([]byte, DecodedLen(len(src)))
  	if _, err := Decode(dst, src); err != nil {
  		return nil, err
  	}
  	return dst, nil
  }
docs: // DecodeString returns the bytes represented by the base128 string s.