public String getExternalId() {
        return this.externalId;
    }
<p>
(Deprecated) Your AWS account ID, which you assigned to an external ID key in an IAM trust policy. Amazon
Pinpoint previously used this value to assume an IAM role when importing endpoint definitions, but we removed
this requirement. We don't recommend use of external IDs for IAM roles that are assumed by Amazon Pinpoint.
</p>

@return (Deprecated) Your AWS account ID, which you assigned to an external ID key in an IAM trust policy. Amazon
        Pinpoint previously used this value to assume an IAM role when importing endpoint definitions, but we
        removed this requirement. We don't recommend use of external IDs for IAM roles that are assumed by Amazon
        Pinpoint.
aws-java-sdk-pinpoint/src/main/java/com/amazonaws/services/pinpoint/model/SegmentImportResource.java