565
569
def check_conversion_target(self, target_format):
566
570
if self.rich_root_data and not target_format.rich_root_data:
567
571
raise errors.BadConversionTarget(
569
574
if (self.supports_tree_reference and
570
575
not getattr(target_format, 'supports_tree_reference', False)):
571
576
raise errors.BadConversionTarget(