commit 65fae6caab5201eca2d43143a7365f8c67efdf13
Author: Sam Napolitano <snapolitano@covermymeds.com>
Date:   Thu Nov 9 20:18:49 2017 -0500

    Strip trailing dot from certificate and hostname

diff --git a/Lib/ssl.py b/Lib/ssl.py
index 75caae0c44..c0493e4064 100644
--- a/Lib/ssl.py
+++ b/Lib/ssl.py
@@ -230,6 +230,12 @@ def _dnsname_match(dn, hostname, max_wildcards=1):
     if not dn:
         return False
 
+    # strip trailing dot
+    if dn[-1] == '.':
+        dn = dn[:-1]
+    if hostname[-1] == '.':
+        hostname = hostname[:-1]
+
     leftmost, *remainder = dn.split(r'.')
 
     wildcards = leftmost.count('*')