/** {@inheritdoc} */
 public function getIterator()
 {
     foreach ($this->collection as $response) {
         $this->profiler->registerResponse($response);
         (yield $response);
     }
 }
 /** {@inheritdoc} */
 public function invoke($calls)
 {
     $this->profiler->registerCalls($calls);
     return new ProfiledResponseCollection($this->client->invoke($calls), $this->profiler);
 }