Return a newly created settings part, containing a default
        `w:settings` element tree.

def default(cls, package):
        """
        Return a newly created settings part, containing a default
        `w:settings` element tree.
        """
        partname = PackURI('/word/settings.xml')
        content_type = CT.WML_SETTINGS
        element = parse_xml(cls._default_settings_xml())
        return cls(partname, content_type, element, package)