How to use the pep8.normalize_paths function in pep8

continue
            if not included_file.startswith((os.sep, './', '~/')):
                included_files.append('./' + included_file)
            else:
                included_files.append(included_file)
        cls.include_in_doctest = pep8.normalize_paths(','.join(included_files))

        excluded_files = []
        for excluded_file in options.exclude_from_doctest.split(','):
            if excluded_file == '':
                continue
            if not excluded_file.startswith((os.sep, './', '~/')):
                excluded_files.append('./' + excluded_file)
            else:
                excluded_files.append(excluded_file)
        cls.exclude_from_doctest = pep8.normalize_paths(
            ','.join(excluded_files))

        inc_exc = set(cls.include_in_doctest).intersection(
            set(cls.exclude_from_doctest))
        if inc_exc:
            raise ValueError('"%s" was specified in both the '
                             'include-in-doctest and exclude-from-doctest '
                             'options. You are not allowed to specify it in '
                             'both for doctesting.' % inc_exc)

def parse_options(cls, options):
        if options.builtins:
            cls.builtIns = cls.builtIns.union(options.builtins.split(','))
        cls.withDoctest = options.doctests

        included_files = []
        for included_file in options.include_in_doctest.split(','):
            if included_file == '':
                continue
            if not included_file.startswith((os.sep, './', '~/')):
                included_files.append('./' + included_file)
            else:
                included_files.append(included_file)
        cls.include_in_doctest = pep8.normalize_paths(','.join(included_files))

        excluded_files = []
        for excluded_file in options.exclude_from_doctest.split(','):
            if excluded_file == '':
                continue
            if not excluded_file.startswith((os.sep, './', '~/')):
                excluded_files.append('./' + excluded_file)
            else:
                excluded_files.append(excluded_file)
        cls.exclude_from_doctest = pep8.normalize_paths(
            ','.join(excluded_files))

        inc_exc = set(cls.include_in_doctest).intersection(
            set(cls.exclude_from_doctest))
        if inc_exc:
            raise ValueError('"%s" was specified in both the '

def get_style_guide(**kwargs):
    """Parse the options and configure the checker. This returns a sub-class
    of ``pep8.StyleGuide``."""
    kwargs['parser'], options_hooks = get_parser()
    styleguide = StyleGuide(**kwargs)
    options = styleguide.options
    _disable_extensions(kwargs['parser'], options)

    if options.exclude and not isinstance(options.exclude, list):
        options.exclude = pep8.normalize_paths(options.exclude)
    elif not options.exclude:
        options.exclude = []

    # Add patterns in EXTRA_EXCLUDE to the list of excluded patterns
    options.exclude.extend(pep8.normalize_paths(EXTRA_EXCLUDE))

    for options_hook in options_hooks:
        options_hook(options)

    if util.warn_when_using_jobs(options):
        if not multiprocessing:
            warnings.warn("The multiprocessing module is not available. "
                          "Ignoring --jobs arguments.")
        if util.is_windows():
            warnings.warn("The --jobs option is not available on Windows. "
                          "Ignoring --jobs arguments.")
        if util.is_using_stdin(styleguide.paths):
            warnings.warn("The --jobs option is not compatible with supplying "
                          "input using - . Ignoring --jobs arguments.")
        if options.diff:
            warnings.warn("The --diff option was specified with --jobs but "

def __init__(self, tree, filename):
        filename = pep8.normalize_paths(filename)[0]
        withDoctest = self.withDoctest
        included_by = [include for include in self.include_in_doctest
                       if include != '' and filename.startswith(include)]
        if included_by:
            withDoctest = True

        for exclude in self.exclude_from_doctest:
            if exclude != '' and filename.startswith(exclude):
                withDoctest = False
                overlaped_by = [include for include in included_by
                                if include.startswith(exclude)]

                if overlaped_by:
                    withDoctest = True

        super(FlakesChecker, self).__init__(tree, filename,

def get_style_guide(**kwargs):
    """Parse the options and configure the checker. This returns a sub-class
    of ``pep8.StyleGuide``."""
    kwargs['parser'], options_hooks = get_parser()
    styleguide = StyleGuide(**kwargs)
    options = styleguide.options
    _disable_extensions(kwargs['parser'], options)

    if options.exclude and not isinstance(options.exclude, list):
        options.exclude = pep8.normalize_paths(options.exclude)
    elif not options.exclude:
        options.exclude = []

    # Add patterns in EXTRA_EXCLUDE to the list of excluded patterns
    options.exclude.extend(pep8.normalize_paths(EXTRA_EXCLUDE))

    for options_hook in options_hooks:
        options_hook(options)

    if util.warn_when_using_jobs(options):
        if not multiprocessing:
            warnings.warn("The multiprocessing module is not available. "
                          "Ignoring --jobs arguments.")
        if util.is_windows():
            warnings.warn("The --jobs option is not available on Windows. "
                          "Ignoring --jobs arguments.")