issues: 298421965

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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
298421965 MDU6SXNzdWUyOTg0MjE5NjU= 1923 Local test failure in test_backends 5635139 closed 0     6 2018-02-19T22:53:37Z 2020-09-05T20:32:17Z 2020-09-05T20:32:17Z MEMBER      

I'm happy to debug this further but before I do, is this an issue people have seen before? I'm running tests on master and hit an issue very early on.

FWIW I don't use netCDF, and don't think I've got that installed

Code Sample, a copy-pastable example if possible

```python ========================================================================== FAILURES ========================================================================== _________ ScipyInMemoryDataTest.test_bytesio_pickle __________

self = <xarray.tests.test_backends.ScipyInMemoryDataTest testMethod=test_bytesio_pickle>

@pytest.mark.skipif(PY2, reason='cannot pickle BytesIO on Python 2')
def test_bytesio_pickle(self):
    data = Dataset({'foo': ('x', [1, 2, 3])})
    fobj = BytesIO(data.to_netcdf())
    with open_dataset(fobj, autoclose=self.autoclose) as ds:

      unpickled = pickle.loads(pickle.dumps(ds))

E TypeError: can't pickle _thread.lock objects

xarray/tests/test_backends.py:1384: TypeError ```

Problem description

[this should explain why the current behavior is a problem and why the expected output is a better solution.]

Expected Output

Skip or pass backends tests

Output of xr.show_versions()

INSTALLED VERSIONS ------------------ commit: d00721a3560f57a1b9226c5dbf5bf3af0356619d python: 3.6.4.final.0 python-bits: 64 OS: Darwin OS-release: 17.4.0 machine: x86_64 processor: i386 byteorder: little LC_ALL: None LANG: en_US.UTF-8 LOCALE: en_US.UTF-8 xarray: 0.7.0-38-g1005a9e # not sure why this is tagged so early. I'm running on latest master pandas: 0.22.0 numpy: 1.14.0 scipy: 1.0.0 netCDF4: None h5netcdf: None h5py: None Nio: None zarr: None bottleneck: 1.2.1 cyordereddict: None dask: None distributed: None matplotlib: 2.1.2 cartopy: None seaborn: 0.8.1 setuptools: 38.5.1 pip: 9.0.1 conda: None pytest: 3.4.0 IPython: 6.2.1 sphinx: None 
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   completed 13221727 issue

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