tensorboard crashes with "locale.Error: unsupported locale setting"

tensorboard 1.9.0
Mac OS High Sierra
Python 3.6.5

$ .venv/bin/tensorboard --logdir runs
Traceback (most recent call last):
  File ".venv/bin/tensorboard", line 11, in <module>
    sys.exit(run_main())
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/site-packages/tensorboard/main.py", line 46, in run_main
    tf.app.run(main)
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/site-packages/tensorflow/python/platform/app.py", line 125, in run
    _sys.exit(main(argv))
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/site-packages/tensorboard/main.py", line 55, in main
    default.get_assets_zip_provider())
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/site-packages/tensorboard/program.py", line 167, in main
    util.setup_logging()
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/site-packages/tensorboard/util.py", line 50, in setup_logging
    locale.setlocale(locale.LC_ALL, '')
  File "/Users/mikesolomon/devel/pytorch-sandbox/.venv/lib/python3.6/locale.py", line 598, in setlocale
    return _setlocale(category, locale)
locale.Error: unsupported locale setting

commenting out util.setup_logging() makes it work like a charm, but this is kinda hacky.
Sorry that I can't contribute a fix, as I'm not exactly sure how the locale affects tensorboard and/or python.

Reproduce the reported command on macOS and start with tensorboard/util.py at util.setup_logging(), where locale.setlocale(locale.LC_ALL, '') raises the exception. Determine how logging should behave when the system locale is unsupported, then verify that TensorBoard starts without the crash and that logging still works.