code: func (g *gRPCService) Decrypt(cipher []byte) ([]byte, error) {
  	ctx, cancel := context.WithTimeout(context.Background(), g.callTimeout)
  	defer cancel()
  
  	if err := g.checkAPIVersion(ctx); err != nil {
  		return nil, err
  	}
  
  	request := &kmsapi.DecryptRequest{Cipher: cipher, Version: kmsapiVersion}
  	response, err := g.kmsClient.Decrypt(ctx, request)
  	if err != nil {
  		return nil, err
  	}
  	return response.Plain, nil
  }
docs: // Decrypt a given data string to obtain the original byte data.