issues: 552896124

The py37-windows CI seems to fail for newer PRs: ```pytb ___ TestPseudoNetCDFFormat.test_uamiv_format_write ____

self = <xarray.tests.test_backends.TestPseudoNetCDFFormat object at 0x000002E11FF2DC08>

def test_uamiv_format_write(self):
fmtkw = {"format": "uamiv"}

expected = open_example_dataset(
        "example.uamiv", engine="pseudonetcdf", backend_kwargs=fmtkw
)
with self.roundtrip(
    expected,
        save_kwargs=fmtkw,
    open_kwargs={"backend_kwargs": fmtkw},
        allow_cleanup_failure=True,
) as actual:

      assert_identical(expected, actual)

xarray\tests\test_backends.py:3532:

xarray\core\formatting.py:628: in diff_dataset_repr summary.append(diff_attrs_repr(a.attrs, b.attrs, compat))

a_mapping = {'CPROJ': 0, 'FILEDESC': 'CAMx ', 'FTYPE': 1, 'GDNAM': 'CAMx ', ...} b_mapping = {'CPROJ': 0, 'FILEDESC': 'CAMx ', 'FTYPE': 1, 'GDNAM': 'CAMx ', ...} compat = 'identical', title = 'Attributes' summarizer = <function summarize_attr at 0x000002E1156813A8>, col_width = None

def _diff_mapping_repr(a_mapping, b_mapping, compat, title, summarizer, col_width=None):
    def extra_items_repr(extra_keys, mapping, ab_side):
        extra_repr = [summarizer(k, mapping[k], col_width) for k in extra_keys]
        if extra_repr:
            header = f"{title} only on the {ab_side} object:"
            return [header] + extra_repr
        else:
            return []

a_keys = set(a_mapping)
    b_keys = set(b_mapping)

    summary = []

diff_items = []

    for k in a_keys & b_keys:
    try:
            # compare xarray variable
            compatible = getattr(a_mapping[k], compat)(b_mapping[k])
            is_variable = True
        except AttributeError:
            # compare attribute value
            compatible = a_mapping[k] == b_mapping[k]
            is_variable = False

      if not compatible:

E ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all() ```