/** The key of the configuration. e.g. 10 */
    String SUGGEST_POPULAR_WORD_SIZE = "suggest.popular.word.size";

    /** The key of the configuration. e.g. 30 */
    String SUGGEST_POPULAR_WORD_WINDOW_SIZE = "suggest.popular.word.window.size";

    /** The key of the configuration. e.g. 10 */
    String SUGGEST_POPULAR_WORD_QUERY_FREQ = "suggest.popular.word.query.freq";

        Cloud TPUs.
    *   Support for `.fit`, `.evaluate`, `.predict` on TPU using numpy data, in
        addition to `tf.data.Dataset`.
    *   Keras reference implementations for many popular models are available in
        the TensorFlow
        [Model Garden](https://github.com/tensorflow/models/tree/master/official).
*   `tf.data`
    *   Changes rebatching for `tf.data datasets` + DistributionStrategy for