From 126b3e17fd3a63dd0a0bcba57e18f9fc914e4d7b Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Thu, 9 Aug 2018 21:22:12 +0100
Subject: [PATCH] Revert #2347 (#2377)

---
 stdlib/2and3/csv.pyi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/stdlib/2and3/csv.pyi b/stdlib/2and3/csv.pyi
index 038e9433d..5511d7d6f 100644
--- a/stdlib/2and3/csv.pyi
+++ b/stdlib/2and3/csv.pyi
@@ -52,9 +52,9 @@ if sys.version_info >= (3,):
         quoting = ...  # type: int
 
 if sys.version_info >= (3, 6):
-    _DRMapping = OrderedDict[str, Optional[str]]
+    _DRMapping = OrderedDict[str, str]
 else:
-    _DRMapping = Dict[str, Optional[str]]
+    _DRMapping = Dict[str, str]
 
 
 class DictReader(Iterator[_DRMapping]):