private synchronized Gmail makeGmailService(TokensAndUrlAuthData authData) {
    Credential credential = credentialFactory.createCredential(authData);
    return new Gmail.Builder(
            credentialFactory.getHttpTransport(), credentialFactory.getJsonFactory(), credential)
        .setApplicationName(GoogleStaticObjects.APP_NAME)
        .build();
  }
Creates the given {@code labelName} in the import service provider and returns the id.
extensions/data-transfer/portability-data-transfer-google/src/main/java/org/datatransferproject/datatransfer/google/mail/GoogleMailImporter.java