def override_missing_value(data, headers, missing_value='<STR_LIT>', **_):
return (([missing_value if v is None else v for v in row] for row in data),<EOL>headers)<EOL>
Override missing values in the *data* with *missing_value*.

    A missing value is any value that is :data:`None`.

    :param iterable data: An :term:`iterable` (e.g. list) of rows.
    :param iterable headers: The column headers.
    :param missing_value: The default value to use for missing data.
    :return: The processed data and headers.
    :rtype: tuple