/**
  * TODO
  *
  * @param \Shockwavemk\Mail\Base\Model\Mail $mail
  *
  * @return TransportBuilder
  * @throws \Magento\Framework\Exception\MailException
  */
 protected function deriveTransportBuilderFromExistingMail($mail)
 {
     return $this->transportBuilder->setTemplateIdentifier($mail->getTemplateIdentifier())->setTemplateOptions(['area' => Area::AREA_FRONTEND, 'store' => $mail->getStoreId()])->setTemplateVars($mail->getVars())->setFrom($mail->getSenderMail());
 }