code: func Decode(d []byte, v interface{}) error {
  	zr, err := zlib.NewReader(bytes.NewReader(d))
  	if err != nil {
  		return errors.Annotate(err, "failed to create zlib Reader").Err()
  	}
  	defer zr.Close()
  
  	if err := json.NewDecoder(zr).Decode(v); err != nil {
  		return errors.Annotate(err, "failed to JSON-decode").Err()
  	}
  	return nil
  }
docs: // Decode is a convenience method for decoding a ZLIB-compressed JSON-encoded
  // object encoded by Encode.