human
I wrote the below code

    class TestHeader(ascii.BasicHeader, ):
        def _set_cols_from_names(self):
            self.cols = [ascii.Column(name=x) for x in self.names]
            for col in self.cols:
                col.fill_values = {'--': '0'}
    class Tester(ascii.Basic, ):
        header_class = TestHeader
    reader = ascii.get_reader(Reader=Tester)
    assert (reader.read('#    Column    definition    is    the    first    uncommented    line\n#    Default    delimiter    is    the    space    character.\na    b    c\n#    Data    starts    after    the    header    column    definition,    blank    lines    ignored\n--    2    3\n4    5    6    ')['a'][0] is np.ma.masked)

What's a good function header?
assistant
#Here's a good function header.

def test_initial_column_fill_values():