Returns the sum of the field in the result set of the query
        by wrapping the query and performing a SUM aggregate of the specified field
        :param field: the field to pass to the SUM aggregate
        :type field: str

        :return: The sum of the specified field
        :rtype: int

def sum(self, field):
        """
        Returns the sum of the field in the result set of the query
        by wrapping the query and performing a SUM aggregate of the specified field
        :param field: the field to pass to the SUM aggregate
        :type field: str

        :return: The sum of the specified field
        :rtype: int
        """
        q = Query(self.connection).from_table(self, fields=[
            SumField(field)
        ])
        rows = q.select(bypass_safe_limit=True)
        return list(rows[0].values())[0]