find usage for security groups

def _find_usage_security_groups(self):
        """find usage for security groups"""
        vpc_count = 0

        paginator = self.conn.get_paginator('describe_db_security_groups')
        for page in paginator.paginate():
            for group in page['DBSecurityGroups']:
                if 'VpcId' in group and group['VpcId'] is not None:
                    vpc_count += 1
                self.limits['Max auths per security group']._add_current_usage(
                    len(group["EC2SecurityGroups"]) + len(group["IPRanges"]),
                    aws_type='AWS::RDS::DBSecurityGroup',
                    resource_id=group['DBSecurityGroupName']
                )

        self.limits['VPC Security Groups']._add_current_usage(
            vpc_count,
            aws_type='AWS::RDS::DBSecurityGroup',
        )