code: protected function getClassFromOperation($name, Operation $operation = null, $reference, $registry)
      {
          if ($operation === null) {
              return;
          }
  
          if ($operation->getParameters()) {
              foreach ($operation->getParameters() as $key => $parameter) {
                  if ($parameter instanceof BodyParameter) {
                      $this->chainGuesser->guessClass($parameter->getSchema(), $name . 'Body', $reference . '/parameters/' . $key,  $registry);
                  }
              }
          }
  
          if ($operation->getResponses()) {
              foreach ($operation->getResponses() as $status => $response) {
                  if ($response instanceof Response) {
                      $this->chainGuesser->guessClass($response->getSchema(), $name.'Response'.$status, $reference . '/responses/' . $status, $registry);
                  }
              }
          }
      }
docs: Discover classes in operation
  
  @param $name
  @param Operation $operation
  @param string $reference
  @param Registry $registry