update html5lib vendoring patch
@@ -29,3 +29,27 @@ index dcfac220..d8b53004 100644
from xml.dom import minidom, Node
import weakref
+diff --git a/src/pip/_vendor/html5lib/_utils.py b/src/pip/_vendor/html5lib/_utils.py
+index 0703afb3..96eb17b2 100644
+--- a/src/pip/_vendor/html5lib/_utils.py
++++ b/src/pip/_vendor/html5lib/_utils.py
+@@ -2,12 +2,15 @@ from __future__ import absolute_import, division, unicode_literals
+
+ from types import ModuleType
+
+-from pip._vendor.six import text_type
++from pip._vendor.six import text_type, PY3
+
+-try:
+- import xml.etree.cElementTree as default_etree
+-except ImportError:
++if PY3:
+ import xml.etree.ElementTree as default_etree
++else:
++ try:
++ import xml.etree.cElementTree as default_etree
++ except ImportError:
++ import xml.etree.ElementTree as default_etree
+
+
+ __all__ = ["default_etree", "MethodDispatcher", "isSurrogatePair",
