private com.google.protobuf.MapField<java.lang.String, java.lang.String>
        internalGetMutableLabels() {
      if (labels_ == null) {
        labels_ = com.google.protobuf.MapField.newMapField(LabelsDefaultEntryHolder.defaultEntry);
      }
      if (!labels_.isMutable()) {
        labels_ = labels_.copy();
      }
      bitField0_ |= 0x00000004;
      onChanged();
      return labels_;
    }
<pre>
Optional. Target project and location to make a call.

Format: `projects/{project-id}/locations/{location-id}`.

If no parent is specified, a region will be chosen automatically.

Supported location-ids:
    `us`: USA country only,
    `asia`: East asia areas, like Japan, Taiwan,
    `eu`: The European Union.

Example: `projects/project-A/locations/eu`.
</pre>

<code>string parent = 4;</code>

@param value The bytes for parent to set.
@return This builder for chaining.
java-vision/proto-google-cloud-vision-v1/src/main/java/com/google/cloud/vision/v1/BatchAnnotateImagesRequest.java