From 34404e3c4ab0ba6410d52e4e02f67b75c3901689 Mon Sep 17 00:00:00 2001
From: "Jessica B. Hamrick" <jhamrick@berkeley.edu>
Date: Thu, 25 Mar 2021 22:05:53 +0000
Subject: [PATCH] Workaround for asyncio issue on windows

---
 nbgrader/apps/nbgraderapp.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/nbgrader/apps/nbgraderapp.py b/nbgrader/apps/nbgraderapp.py
index ba648fd7b..38696a238 100755
--- a/nbgrader/apps/nbgraderapp.py
+++ b/nbgrader/apps/nbgraderapp.py
@@ -4,6 +4,7 @@
 import sys
 import os
 
+import asyncio
 from textwrap import dedent
 
 from traitlets import default
@@ -327,4 +328,8 @@ def print_version(self):
 
 
 def main():
+    # See https://bugs.python.org/issue37373 :(
+    # Workaround from https://github.com/jupyter/nbconvert/issues/1372
+    if sys.version_info[0] == 3 and sys.version_info[1] >= 8 and sys.platform.startswith('win'):
+        asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
     NbGraderApp.launch_instance()