/** The key of the configuration. e.g. url */
    String INDEX_FIELD_URL = "index.field.url";

    /** The key of the configuration. e.g. doc_id */
    String INDEX_FIELD_doc_id = "index.field.doc_id";

    /** The key of the configuration. e.g. _id */
    String INDEX_FIELD_ID = "index.field.id";

    /** The key of the configuration. e.g. _version */

    change, but please check the
    [API doc](https://www.tensorflow.org/api_docs/python/tf/keras/optimizers/experimental)
    if any API used in your workflow is changed or deprecated, and make
    adaptations. If you decide to keep using the old optimizer, please
    explicitly change your optimizer to `tf.keras.optimizers.legacy.Optimizer`.
*   RNG behavior change for `tf.keras.initializers`. Keras initializers will now