public java.util.List<IpPermission> getUnknownIpPermissions() {
        if (unknownIpPermissions == null) {
            unknownIpPermissions = new com.amazonaws.internal.SdkInternalList<IpPermission>();
        }
        return unknownIpPermissions;
    }
<p>
The outbound rules that were unknown to the service. In some cases, <code>unknownIpPermissionSet</code> might be
in a different format from the request parameter.
</p>

@return The outbound rules that were unknown to the service. In some cases, <code>unknownIpPermissionSet</code>
        might be in a different format from the request parameter.
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/RevokeSecurityGroupEgressResult.java