code: def _process_fields_convert_map(self, parameters, download=False):
          
          if 'fields_convert_map' in parameters:
              _f = parameters.get('fields_convert_map') or []
              parameters['fields_convert_map'] = self._get_fields_convert_map(_f, download)
docs: process fields_convert_map, ListView doesn't support list type but dict
  
          fields_convert_map should be define as list or dict
          for list, it can be:
              [name, name, ...]
              [(name, func), (name, func), ...] if func is str, it'll be the property name of class
          for dict, it can be:
              {'name':func, ...}
          :param model: model object
          :param parameters:
          :param prefix: it'll used to combine prefix+_convert_xxx to get convert function
              from class
          :return: