From ae7f61243d06ffb29ca1f6396bed4bc285e55a28 Mon Sep 17 00:00:00 2001
From: speedplane <michael.sander@docketalarm.com>
Date: Wed, 19 Dec 2018 06:14:38 -0500
Subject: [PATCH] App Engine does not have _tunnel_host set in its httplib
 implementation. Make sure we check for that. #1503. Not this reverts part of
 the change in #1430.

---
 src/urllib3/connection.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/urllib3/connection.py b/src/urllib3/connection.py
index ba269b7a13..e03ef0cf67 100644
--- a/src/urllib3/connection.py
+++ b/src/urllib3/connection.py
@@ -171,7 +171,7 @@ def _new_conn(self):
 
     def _prepare_conn(self, conn):
         self.sock = conn
-        if self._tunnel_host:
+        if getattr(self, '_tunnel_host', None):
             # TODO: Fix tunnel so it doesn't depend on self.sock state.
             self._tunnel()
             # Mark this connection as not reusable
@@ -301,7 +301,8 @@ def connect(self):
         conn = self._new_conn()
         hostname = self.host
 
-        if self._tunnel_host:
+        # Google App Engine's different HTTP lib may not define_tunnel_host.
+        if getattr(self, '_tunnel_host', None):
             self.sock = conn
             # Calls self._set_hostport(), so self.host is
             # self._tunnel_host below.