code: func (k *Keygen) GetNewKeyPairFromPool() ([]byte, []byte, error) {
  	select {
  	case key := <-k.keysCh:
  		return key.privPem, key.pubBytes, nil
  	default:
  		return GenerateKeyPair("")
  	}
  }
docs: // GetNewKeyPairFromPool returns precomputed key pair from the pool.