@classmethod
def add_options(cls, parser):
    """Register options for PyFlakes on the Flake8 OptionManager."""
    parser.add_option('--builtins', parse_from_config=True,
        comma_separated_list=True, help=
        'define more built-ins, comma separated')
    parser.add_option('--doctests', default=False, action='store_true',
        parse_from_config=True, help='check syntax of the doctests')
    parser.add_option('--include-in-doctest', default='', dest=
        'include_in_doctest', parse_from_config=True, comma_separated_list=
        True, normalize_paths=True, help='Run doctests only on these files',
        type='string')
    parser.add_option('--exclude-from-doctest', default='', dest=
        'exclude_from_doctest', parse_from_config=True,
        comma_separated_list=True, normalize_paths=True, help=
        'Skip these files when running doctests', type='string')
