/** The key of the configuration. e.g. java */
    String JAVA_COMMAND_PATH = "java.command.path";

    /** The key of the configuration. e.g. python */
    String PYTHON_COMMAND_PATH = "python.command.path";

    /** The key of the configuration. e.g. UTF-8 */
    String PATH_ENCODING = "path.encoding";

    /** The key of the configuration. e.g. true */
    String USE_OWN_TMP_DIR = "use.own.tmp.dir";

        `tf.keras.optimizer.Optimizer.apply_gradients`. This allows custom
        gradient aggregation and processing aggregated gradients in custom
        training loop.
    *   Allow `pathlib.Path` paths for loading models via Keras API.
*   `tf.function`/AutoGraph:
    *   AutoGraph is now available in `ReplicaContext.merge_call`,
        `Strategy.extended.update` and `Strategy.extended.update_non_slot`.

* Fix support for *paths* in *path parameters* without needing explicit `Path(...)`.
    * PR [#256](https://github.com/tiangolo/fastapi/pull/256).
    * Documented in PR [#272](https://github.com/tiangolo/fastapi/pull/272) by [@wshayes](https://github.com/wshayes).
    * New documentation at: [Path Parameters containing paths](https://fastapi.tiangolo.com/tutorial/path-params/#path-parameters-containing-paths).