tensorboard: HParams plugin ModuleNotFoundError v1.13.1

Installing Tensorflow/board v1.13.1 via pip, it seems like the pip package is missing the HParams plugin.

Importing it from tensorboard.plugins import hparams I get a ModuleNotFoundError: No module named 'tensorboard.plugins.hparams'

But the module is in the release branch of 1.13.0 here on GitHub? Am I missing something? @wchargin can shed some light? why is the HParams plugin not included in the build?

• TensorBoard version: v1.13.0
• OS Platform and version Ubuntu 16.04
• Python version v3.6.8

help(tensorboard.plugins)

Help on package tensorboard.plugins in tensorboard:

NAME
    tensorboard.plugins

PACKAGE CONTENTS
    audio (package)
    base_plugin
    beholder (package)
    core (package)
    custom_scalar (package)
    debugger (package)
    distribution (package)
    graph (package)
    histogram (package)
    image (package)
    interactive_inference (package)
    pr_curve (package)
    profile (package)
    projector (package)
    scalar (package)
    text (package)