issues: 800678839

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id node_id number title user state locked assignee milestone comments created_at updated_at closed_at author_association active_lock_reason draft pull_request body reactions performed_via_github_app state_reason repo type
800678839 MDU6SXNzdWU4MDA2Nzg4Mzk= 4859 Unicode strings unexpectedly transformed to byte strings upon `open_dataset` 38673295 closed 0     7 2021-02-03T20:34:27Z 2021-11-20T17:58:34Z 2021-11-20T17:58:34Z NONE      

What happened:

Unicode coordinates convert to bytes after saving/loading with h5netcdf backend. This results with the practically unusable dataset (bytes != string).

What you expected to happen:

Load the string as a string.

Minimal Complete Verifiable Example:

```python coils = np.array(["A", "B", "C", "D", "E"]) data = np.array([1 + 1j, 1 + 2j, 3j, 4j, 6j])

test_ds = xr.Dataset() test_ds.coords["coils"] = coils test_ds["data"] = ("coils", data) test_ds

<xarray.Dataset> Dimensions: (coils: 5) Coordinates: * coils (coils) <U1 'A' 'B' 'C' 'D' 'E' Data variables: data (coils) complex128 (1+1j) (1+2j) 3j 4j 6j

test_ds.to_netcdf("test.nc", engine="h5netcdf") del test_ds test_ds = xr.open_dataset("test.nc", engine="h5netcdf") test_ds

<xarray.Dataset> Dimensions: (coils: 5) Coordinates: * coils (coils) object b'A' b'B' b'C' b'D' b'E' Data variables: data (coils) complex128 ...

```

Anything else we need to know?:

The issue may be related to #1638.

Environment:

Output of <tt>xr.show_versions()</tt> INSTALLED VERSIONS ------------------ commit: None python: 3.8.6 | packaged by conda-forge | (default, Oct 7 2020, 19:08:05) [GCC 7.5.0] python-bits: 64 OS: Linux OS-release: 5.4.0-65-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: cs_CZ.UTF-8 LOCALE: cs_CZ.UTF-8 libhdf5: 1.10.5 libnetcdf: 4.6.3 xarray: 0.16.2 pandas: 1.1.5 numpy: 1.19.4 scipy: 1.5.3 netCDF4: 1.5.5 pydap: None h5netcdf: 0.8.1 h5py: 3.1.0 Nio: None zarr: None cftime: 1.3.0 nc_time_axis: None PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: 1.3.2 dask: 2020.12.0 distributed: 2020.12.0 matplotlib: 3.3.3 cartopy: None seaborn: 0.11.0 numbagg: None pint: 0.16.1 setuptools: 49.6.0.post20201009 pip: 20.3.3 conda: None pytest: 6.2.1 IPython: 7.19.0 sphinx: None 
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   completed 13221727 issue

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