code: func (s *StatusCode) MarshalBinary() ([]byte, error) {
  	// 2 bytes: status code
  	// N bytes: message
  	b := buffer.New(nil)
  	b.Write16(uint16(s.Code))
  	b.WriteBytes([]byte(s.Message))
  	return b.Data(), nil
  }
docs: // MarshalBinary allocates a byte slice containing the data from a StatusCode.