def _populate(self, fields):
schema = self.schema<EOL>for k, v in fields.items():<EOL><INDENT>fields[k] = schema.fields[k].iget(self, v)<EOL><DEDENT>self.modify(fields)<EOL>self.reset_modified()<EOL>
this runs all the fields through their iget methods to mimic them
        freshly coming out of the db, then resets modified

        :param fields: dict, the fields that were passed in