Function key

dask/tests/test_delayed.py:739–743

(s)

    assert set(x.dask).issubset(v.dask)

    def key(s):
        if isinstance(s, tuple):
            s = s[0]
        # Ignore _ in 'ones_like'
        return s.split("-")[0].replace("_", "")

    assert all(key(k).isalpha() for k in v.dask)