code: def set_field_value(self, field_name, value):
          
          if self.response is None:
              return
  
          if 'data' in self.response:
              items = self.response['data']
          else:
              items = [self.response]
  
          for item in items:
              item[field_name] = value
docs: Set value of response field named `field_name`.
  
          If response contains single item, its field is set.
          If response contains multiple items, all the items in response
          are edited.
          To edit response meta(e.g. 'count') edit response directly at
          `event.response`.
  
          :param field_name: Name of response field value of which should
              be set.
          :param value: Value to be set.