private com.google.protobuf.MapField<java.lang.String, java.lang.String> internalGetModels() {
    if (models_ == null) {
      return com.google.protobuf.MapField.emptyMapField(ModelsDefaultEntryHolder.defaultEntry);
    }
    return models_;
  }
<pre>
Required. Specify up to 10 language codes here.
</pre>

<code>repeated string target_language_codes = 3 [(.google.api.field_behavior) = REQUIRED];
</code>

@param index The index of the value to return.
@return The bytes of the targetLanguageCodes at the given index.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/BatchTranslateTextRequest.java