`tf.distribute.InputOptions` for specific options when used with
        distribution.
    *   `tf.keras.experimental.SidecarEvaluator` is now available for a program
        intended to be run on an evaluator task, which is commonly used to
        supplement a training cluster running with
        `tf.distribute.experimental.ParameterServerStrategy` (see
        `https://www.tensorflow.org/tutorials/distribute/parameter_server_training).