From 4775280c97925fb007657fceef12cf24a7d91ea4 Mon Sep 17 00:00:00 2001
From: Sebastian Rittau <srittau@rittau.biz>
Date: Fri, 23 Mar 2018 14:20:20 +0100
Subject: [PATCH] traceback.print_exception(): Arguments optional in Python 3

---
 stdlib/2and3/traceback.pyi | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/stdlib/2and3/traceback.pyi b/stdlib/2and3/traceback.pyi
index 07f158d6d29b..29bdf67d24e5 100644
--- a/stdlib/2and3/traceback.pyi
+++ b/stdlib/2and3/traceback.pyi
@@ -10,7 +10,8 @@ _PT = Tuple[str, int, str, Optional[str]]
 def print_tb(tb: Optional[TracebackType], limit: Optional[int] = ...,
              file: Optional[IO[str]] = ...) -> None: ...
 if sys.version_info >= (3,):
-    def print_exception(etype: Type[BaseException], value: BaseException,
+    def print_exception(etype: Optional[Type[BaseException]],
+                        value: Optional[BaseException],
                         tb: Optional[TracebackType], limit: Optional[int] = ...,
                         file: Optional[IO[str]] = ...,
                         chain: bool = ...) -> None: ...