code: def highlight(self, *fields, **kwargs):
          
          s = self._clone()
          for f in fields:
              s._highlight[f] = kwargs
          return s
docs: Request highlighting of some fields. All keyword arguments passed in will be
          used as parameters for all the fields in the ``fields`` parameter. Example::
  
              Search().highlight('title', 'body', fragment_size=50)
  
          will produce the equivalent of::
  
              {
                  "highlight": {
                      "fields": {
                          "body": {"fragment_size": 50},
                          "title": {"fragment_size": 50}
                      }
                  }
              }
  
          If you want to have different options for different fields you can call ``highlight`` twice::
  
              Search().highlight('title', fragment_size=50).highlight('body', fragment_size=100)
  
          which will produce::
  
              {
                  "highlight": {
                      "fields": {
                          "body": {"fragment_size": 100},
                          "title": {"fragment_size": 50}
                      }
                  }
              }