fix black formatting

TomNicholas · TomNicholas · commit 68566f31f6b8 · 2020-05-13T16:49:19.000+01:00
diff --git a/xarray/tests/test_backends.py b/xarray/tests/test_backends.py
@@ -3007,9 +3007,7 @@ def test_open_mfdataset_concat_dim_default_none(self):
                 data = Dataset({"x": 0})
                 data.to_netcdf(tmp1)
                 Dataset({"x": np.nan}).to_netcdf(tmp2)
-                with open_mfdataset(
-                    [tmp1, tmp2], combine="nested"
-                ) as actual:
+                with open_mfdataset([tmp1, tmp2], combine="nested") as actual:
                     assert_identical(data, actual)
 
     def test_open_dataset(self):
