def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def delete_lines(self, min_row, max_row):
        if min_row == -1:
            self.current_label.fuzz_values = self.current_label.fuzz_values[:-1]
        else:
            self.current_label.fuzz_values = self.current_label.fuzz_values[:min_row] + self.current_label.fuzz_values[
                                                                                        max_row + 1:]

        _ = self.current_label  # if user deleted all, this will restore a fuzz value

        self.fuzz_table_model.update()