Arviz: xarray 0.16.1 breaks compatibility

[kiudee]

Describe the bug
arviz.utils.HtmlTemplate depends on xarray.core.formatting_html.CSS_STYLE:
https://github.com/arviz-devs/arviz/blob/aab82191677c0ead4cceee3a0198f0afcd7313a4/arviz/utils.py#L700
This was just removed in 0.16.1 of xarray. Here is the corresponding pull request:
https://github.com/pydata/xarray/pull/4297

To Reproduce

1. Install arviz==0.9.0 and xarray==0.16.1.
2. import arviz

Expected behavior
No error during import.

Additional context
arviz==0.9.0 and xarray==0.16.1.
Happens on both Windows and Linux.

[ahartikainen]

We are going to make a new release soon, so this is probably going to be only a small annoyance until we have release ready.

[ahartikainen]

fixed by #1389

[nicospinu]

Hi, the issue still persists on macOS Catalina v.10.15.6 giving the same message as described by kiudee. Shall I create a new issue?

[ahartikainen]

have you tried installing from github

pip install git+https://github.com/arviz-devs/arviz

[kiudee]

@nicospinu the fix is not yet on PyPI (still v0.9.0) there.

[nicospinu]

have you tried installing from github

pip install git+https://github.com/arviz-devs/arviz

Thank you!
The Arviz gets installed together with Pymc3 v3.9.3 and gives the error. Shall I wait until the fix is on PyPI?

[ahartikainen]

then you can do

pip install xarray==0.16.0 -U

[nicospinu]

Thank you so much! It works