'alert if non-vpc RDS SG contains RFC1918 CIDRS'

def check_rds_ec2_rfc1918(self, sg_item):

    tag = 'Non-VPC    RDS    Security    Group    contains    private    RFC-1918    CIDR'
    severity = 8
    if sg_item.config.get('vpc_id', None):
        return
    for ipr in sg_item.config.get('ip_ranges', []):
        cidr = ipr.get('cidr_ip', None)
        if (cidr and check_rfc_1918(cidr)):
            self.add_issue(severity, tag, sg_item, notes=cidr)
