code: public function toXML( XMLWriter $XMLWriter )
      {
          $XMLWriter->startElement( 'Passageiro' );
  
          if ($this->name) {
              $XMLWriter->writeElement( 'Nome', $this->name );
          } else {
              throw new RequiredFieldException( 'Field Nome of the Passenger object is required' );
          }
  
          if ($this->frequentFlyerCard) {
              $XMLWriter->writeElement( 'ProgramaFidelidade', $this->frequentFlyerCard );
          }
  
          if ($this->legalDocumentType) {
              $XMLWriter->writeElement( 'TipoDocumentoLegal', $this->legalDocumentType );
          } else {
              throw new RequiredFieldException( 'Field LegalDocumentType of the Passenger object is required' );
          }
  
          if ($this->legalDocument) {
              $XMLWriter->writeElement( 'DocumentoLegal', $this->legalDocument );
          } else {
              throw new RequiredFieldException( 'Field LegalDocument of the Passenger object is required' );
          }
  
          $XMLWriter->endElement();
      }
docs: @param  \XMLWriter $XMLWriter
  
  @throws \RodrigoPedra\ClearSaleID\Exception\RequiredFieldException