docs: def _get_model_fields(self, model, prefix=_field_prefix):
          """
          Find all fields of given model that are not default models.
          """
          fields = list()
          for field_name, field in model()._ordered_fields:
              # Filter the default fields
              if field_name not in getattr(model, '_DEFAULT_BASE_FIELDS', []):
                  type_name = utils.to_camel(field.solr_type)
                  required = self._marker_true if field.required is True else self._marker_false
                  fields.append((prefix, field_name, type_name, required))
  
          return fields