class SecurityGroup {

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj instanceof SecurityGroup) {
            final SecurityGroup that = (SecurityGroup) obj;
            return this.getClass() == that.getClass()
                    && Objects.equals(this.securityGroup, that.securityGroup);
        }
        return false;
    }

    private  SecurityGroup(String securityGroup);

}