import.
*   Breaking change to `tf.contrib.data.Dataset` APIs that expect a nested
    structure. Lists are now converted to `tf.Tensor` implicitly. You may need
    to change uses of lists to tuples in existing code. In addition, dicts are
    now supported as a nested structure.

## Changes to contrib APIs

*   Adds tf.contrib.nn.rank_sampled_softmax_loss, a sampled-softmax variant that

### Structured logging

SIG Instrumentation standardized the structure of log messages and references to Kubernetes objects. Structured logging makes parsing, processing, storing, querying and analyzing logs easier. New methods in the klog library enforce log message structure.

### EndpointSlices are now enabled by default