*   `Estimator.export_savedmodel` has been renamed to `export_saved_model`.
    *   When saving to SavedModel, Estimators will strip default op attributes.
        This is almost always the correct behavior, as it is more forwards
        compatible, but if you require that default attributes to be saved with
        the model, please use `tf.compat.v1.Estimator`.
    *   Feature Columns have been upgraded to be more Eager-friendly and to work

        * Before this, the return content was first passed through `jsonable_encoder` to ensure it was a "jsonable" object, like a `dict`, instead of an arbitrary object with attributes (like an ORM model). That's why you should make sure to update your Pydantic models for objects with attributes to use `orm_mode = True`.
        * If you don't have a `response_model`, the return object will still be passed through `jsonable_encoder` first.