code: final public function reserve(): ?BaseJob
      {
          $this->beforeWork();
  
          $this->logger->debug('Attempting to reserve a job using {reserver} reserver', [
              'reserver' => $this->getDescription(),
          ]);
  
          for ($i = 0; $i < $this->numQueues; ++$i) {
              $queue = $this->nextQueue();
  
              /** @var \Qless\Jobs\BaseJob|null $job */
              $job = $queue->pop($this->worker);
              if ($job !== null) {
                  $this->logger->info('Found a job on {queue}', ['queue' => (string) $queue]);
                  return $job;
              }
          }
  
          return null;
      }
docs: {@inheritdoc}
  
  @return BaseJob|null