def reset_modified(self):
self.modified_fields = set()<EOL>for field_name, field in self.schema.normal_fields.items():<EOL><INDENT>if isinstance(field, ObjectField):<EOL><INDENT>self.modified_fields.add(field_name)<EOL><DEDENT><DEDENT>
reset field modification tracking

this is handy for when you are loading a new Orm with the results from a query and
you don't want set() to do anything, you can Orm(**fields) and then orm.reset_modified() to
clear all the passed in fields from the modified list