title: for x,y in function(): - Explain the python for loop structure
body: <p>Anyone please explain the line of code</p>
  
  <pre><code>    es_question = (q.as_elasticsearch_dict() for q in questions)
      for ok, result in streaming_bulk(
          get_client(),
          es_question,
          index = settings.ES_INDEX,
          raise_on_error = False
      ):
          if not ok:
              all_ok = False
              action, result = result.popitem()
              logger.error(FAILED_TO_LOAD_ERROR.format(result['_id'], result))
  </code></pre>
  
  <p>I want to know what the for loop does on es_questions and the explanation for line of code below es_question </p>