code: func (whisper *Whisper) GenerateSymKey() (string, error) {
  	key, err := generateSecureRandomData(aesKeyLength)
  	if err != nil {
  		return "", err
  	} else if !validateDataIntegrity(key, aesKeyLength) {
  		return "", fmt.Errorf("error in GenerateSymKey: crypto/rand failed to generate random data")
  	}
  
  	id, err := GenerateRandomID()
  	if err != nil {
  		return "", fmt.Errorf("failed to generate ID: %s", err)
  	}
  
  	whisper.keyMu.Lock()
  	defer whisper.keyMu.Unlock()
  
  	if whisper.symKeys[id] != nil {
  		return "", fmt.Errorf("failed to generate unique ID")
  	}
  	whisper.symKeys[id] = key
  	return id, nil
  }
docs: // GenerateSymKey generates a random symmetric key and stores it under id,
  // which is then returned. Will be used in the future for session key exchange.