def djfrontend_jquery_datatables_themeroller(version=None):
    """
    Returns the jQuery DataTables ThemeRoller CSS file according to version number.
    """
    if version is None:
        if not getattr(settings, 'DJFRONTEND_JQUERY_DATATABLES_THEMEROLLER', False):
            version = getattr(settings, 'DJFRONTEND_JQUERY_DATATABLES_VERSION', DJFRONTEND_JQUERY_DATATABLES_VERSION_DEFAULT)
        else:
            version = getattr(settings, 'DJFRONTEND_JQUERY_DATATABLES_THEMEROLLER', DJFRONTEND_JQUERY_DATATABLES_VERSION_DEFAULT)

    return format_html(
        '<link rel="stylesheet" href="href="{static}djfrontend/css/jquery/jquery.dataTables/{v}/jquery.dataTables_themeroller.min.css">',
        static=_static_url, v=version)
Returns the jQuery DataTables ThemeRoller CSS file according to version number.