How to use the qdarkstyle.palette.DarkPalette function in QDarkStyle

def _apply_application_patches(QCoreApplication, QPalette, QColor):
    """
    Apply application level fixes on the QPalette.

    The import names args must be passed here because the import is done
    inside the load_stylesheet() function, as QtPy is only imported in
    that moment for setting reasons.
    """
    # See issue #139
    color = DarkPalette.COLOR_SELECTION_LIGHT
    qcolor = QColor(color)

    # Todo: check if it is qcoreapplication indeed
    app = QCoreApplication.instance()

    _logger.info("Found application patches to be applied.")

    if app:
        palette = app.palette()
        palette.setColor(QPalette.Normal, QPalette.Link, qcolor)
        app.setPalette(palette)
    else:
        _logger.warn("No QCoreApplication instance found. "
                     "Application patches not applied. "

Returns:
        str: stylesheet string (css).
    """
    os_fix = ""

    if platform.system().lower() == 'darwin':
        # See issue #12
        os_fix = '''
        QDockWidget::title
        {{
            background-color: {color};
            text-align: center;
            height: 12px;
        }}
        '''.format(color=DarkPalette.COLOR_BACKGROUND_NORMAL)

    # Only open the QSS file if any patch is needed
    if os_fix:
        _logger.info("Found OS patches to be applied.")

    return os_fix

if os.path.isdir(theme_root_path):
        shutil.rmtree(theme_root_path)

    shutil.copytree(RC_PATH, theme_rc_path)

    # Copy QSS folder and contents
    theme_qss_path = os.path.join(theme_root_path, qss_loc)

    if os.path.isdir(theme_qss_path):
        os.removedirs(theme_qss_path)

    shutil.copytree(QSS_PATH, theme_qss_path)

    # Create custom palette
    custom_palette = type(name, (DarkPalette, ), {})
    custom_palette.COLOR_BACKGROUND_LIGHT = color_background_light
    custom_palette.COLOR_BACKGROUND_NORMAL = color_background_normal
    custom_palette.COLOR_BACKGROUND_DARK = color_background_dark
    custom_palette.COLOR_FOREGROUND_LIGHT = color_foreground_light
    custom_palette.COLOR_FOREGROUND_NORMAL = color_foreground_normal
    custom_palette.COLOR_FOREGROUND_DARK = color_foreground_dark
    custom_palette.COLOR_SELECTION_LIGHT = color_selection_light
    custom_palette.COLOR_SELECTION_NORMAL = color_selection_normal
    custom_palette.COLOR_SELECTION_DARK = color_selection_dark
    custom_palette.SIZE_BORDER_RADIUS = border_radius
    custom_palette.PATH_RESOURCES = "'{}'".format(theme_root_path)

    # Process images and save them to the custom platte rc folder
    create_images(rc_path=theme_rc_path, palette=custom_palette)
    create_palette_image(path=theme_root_path, palette=custom_palette)

def create_qss(qss_filepath=QSS_FILEPATH, main_scss_filepath=MAIN_SCSS_FILEPATH,
               variables_scss_filepath=VARIABLES_SCSS_FILEPATH,
               palette=DarkPalette):
    """Create variables files and run qtsass compilation."""
    _create_scss_variables(variables_scss_filepath, palette)
    stylesheet = _create_qss(main_scss_filepath, qss_filepath)

    return stylesheet

def create_palette_image(base_svg_path=SVG_PATH, path=IMAGES_PATH,
                         palette=DarkPalette):
    """
    Create palette image svg and png image on specified path.
    """
    # Needed to use QPixmap
    _ = QApplication([])

    base_palette_svg_path = os.path.join(base_svg_path, 'base_palette.svg')
    palette_svg_path = os.path.join(path, 'palette.svg')
    palette_png_path = os.path.join(path, 'palette.png')

    _logger.info("Creating palette image ...")
    _logger.info("Base SVG: %s" % base_palette_svg_path)
    _logger.info("To SVG: %s" % palette_svg_path)
    _logger.info("To PNG: %s" % palette_png_path)

    with open(base_palette_svg_path, 'r') as fh:

def create_images(base_svg_path=SVG_PATH, rc_path=RC_PATH,
                  palette=DarkPalette):
    """Create resources `rc` png image files from base svg files and palette.

    Search all SVG files in `base_svg_path` excluding IMAGE_BLACKLIST,
    change its colors using `palette` creating temporary SVG files, for each
    state generating PNG images for each size `heights`.

    Args:
        base_svg_path (str, optional): [description]. Defaults to SVG_PATH.
        rc_path (str, optional): [description]. Defaults to RC_PATH.
        palette (DarkPalette, optional): Palette . Defaults to DarkPalette.
    """

    # Needed to use QPixmap
    _ = QApplication([])

    temp_dir = tempfile.mkdtemp()