@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    for (int i = 0; i < models_.size(); i++) {
      output.writeMessage(1, models_.get(i));
    }
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(nextPageToken_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 2, nextPageToken_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
A token to retrieve next page of results.
Pass this token to the page_token field in the ListModelsRequest to
obtain the corresponding page.
</pre>

<code>string next_page_token = 2;</code>

@return The bytes for nextPageToken.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/ListModelsResponse.java