From 473e25b2f602f95768a16ef685fed379b4240e23 Mon Sep 17 00:00:00 2001
From: "A. Jesse Jiryu Davis" <jesse@mongodb.com>
Date: Wed, 2 Aug 2017 16:06:16 -0400
Subject: [PATCH] PYTHON-1327 - Handle null username or password

---
 pymongo/common.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pymongo/common.py b/pymongo/common.py
index d0d1ea7dc..60b41d126 100644
--- a/pymongo/common.py
+++ b/pymongo/common.py
@@ -509,8 +509,8 @@ KW_VALIDATORS = {
     'read_preference': validate_read_preference,
     'event_listeners': _validate_event_listeners,
     'tzinfo': validate_tzinfo,
-    'username': validate_string,
-    'password': validate_string,
+    'username': validate_string_or_none,
+    'password': validate_string_or_none,
 }
 
 URI_VALIDATORS.update(TIMEOUT_VALIDATORS)