code: protected function execute(InputInterface $input, OutputInterface $output): void
      {
          $path = $this->projectDir.'/.env';
  
          if (!file_exists($path)) {
              return;
          }
  
          $vars = (new Dotenv())->parse(file_get_contents($path));
          $key = $input->getArgument('key');
  
          if (!$key) {
              $output->write(json_encode($vars));
          }
  
          if (isset($vars[$key])) {
              $output->write($vars[$key]);
          }
      }
docs: {@inheritdoc}