+        bootstrap_node = doc.find(_add_ns('bootstrapInfo'))
+        if bootstrap_node.text is None:
+            bootstrap_url = compat_urlparse.urljoin(
+                base_url, bootstrap_node.attrib['url'])
+            bootstrap = self.ydl.urlopen(bootstrap_url).read()
+        else:
+            bootstrap = base64.b64decode(bootstrap_node.text)