code: def script_fields(self, **kwargs):
          
          s = self._clone()
          for name in kwargs:
              if isinstance(kwargs[name], string_types):
                  kwargs[name] = {'script': kwargs[name]}
          s._script_fields.update(kwargs)
          return s
docs: Define script fields to be calculated on hits. See
          https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-script-fields.html
          for more details.
  
          Example::
  
              s = Search()
              s = s.script_fields(times_two="doc['field'].value * 2")
              s = s.script_fields(
                  times_three={
                      'script': {
                          'inline': "doc['field'].value * params.n",
                          'params': {'n': 3}
                      }
                  }
              )