'download the schema'

def download(self, options):

    url = self.location
    try:
        if ('://' not in url):
            url = urljoin(self.schema.baseurl, url)
        reader = DocumentReader(options)
        d = reader.open(url)
        root = d.root()
        root.set('url', url)
        self.__applytns(root)
        return self.schema.instance(root, url, options)
    except TransportError:
        msg = ('include    schema    at    (%s),    failed' % url)
        log.error('%s,    %s', self.id, msg, exc_info=True)
        raise Exception(msg)
