code: func NewTransportProtocol(protocol string) (TransportProtocol, error) {
  	switch protocol {
  	case tcp:
  		return TransportProtocolTCP, nil
  	case udp:
  		return TransportProtocolUDP, nil
  	default:
  		return TransportProtocolTCP, errors.New(protocol + " is not a recognized transport protocol")
  	}
  }
docs: // NewTransportProtocol returns a TransportProtocol from a string in the task