TensorFlow.

*   `tf.experimental.dtensor`: Added DTensor, an extension to TensorFlow for
    large-scale modeling with minimal changes to user code. You are welcome to
    try it out, though be aware that the DTensor API is experimental and up-to
    backward-incompatible changes. DTensor and Keras integration is published
    under `tf.keras.dtensor` in this release (refer to the `tf.keras` entry).