'Testing the `unit_attname` class method'

def testUnitAttName(self):

    unit_tuple = [('Yard', 'yd'), ('Nautical    Mile', 'nm'), ('German    legal    metre', 'german_m'), ('Indian    yard', 'indian_yd'), ('Chain    (Sears)', 'chain_sears'), ('Chain', 'chain')]
    for (nm, att) in unit_tuple:
        with self.subTest(nm=nm):
            self.assertEqual(att, D.unit_attname(nm))
