def _clone_contrib_fields(self, new_event): attrs = get_simple_column_attrs(ContributionField) - {'field_data'} for old_contrib_field in self.old_event.contribution_fields: contrib_field = ContributionField() contrib_field.populate_from_attrs(old_contrib_field, attrs) contrib_field.field_data = deepcopy(old_contrib_field.field_data) new_event.contribution_fields.append(contrib_field) self._contrib_field_map[old_contrib_field] = contrib_field