code: func Encrypt(data []byte, key []byte) []byte {
  	if data == nil || len(data) == 0 {
  		return data
  	}
  	return toBytes(encrypt(toUint32s(data, true), toUint32s(key, false)), false)
  }
docs: // Encrypt the data with key.
  // data is the bytes to be encrypted.
  // key is the encrypt key. It is the same as the decrypt key.