fixed obvious bug in _send_header as per SF bug #831271
(same as commit of Sun Nov 2 to the release23-maint branch)
diff --git a/Lib/httplib.py b/Lib/httplib.py
index 9832e47..a6ab647 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -727,8 +727,7 @@
# If headers already contains a host header, then define the
# optional skip_host argument to putrequest(). The check is
# harder because field names are case insensitive.
- if 'Host' in (headers
- or [k for k in headers.iterkeys() if k.lower() == "host"]):
+ if 'host' in [k.lower() for k in headers]:
self.putrequest(method, url, skip_host=1)
else:
self.putrequest(method, url)