From 8a12ea9c110c6ce0e5ea12b2a6a82c7ab68ade06 Mon Sep 17 00:00:00 2001
From: Thomas Kluyver <thomas@kluyver.me.uk>
Date: Mon, 13 Sep 2021 14:58:41 +0100
Subject: [PATCH 1/2] Close new event loops in just_run helper

---
 nbclient/util.py | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/nbclient/util.py b/nbclient/util.py
index 9b672357..bafcb778 100644
--- a/nbclient/util.py
+++ b/nbclient/util.py
@@ -37,24 +37,29 @@ def just_run(coro: Awaitable) -> Any:
     """Make the coroutine run, even if there is an event loop running (using nest_asyncio)"""
     # original from vaex/asyncio.py
     loop = asyncio._get_running_loop()
-    if loop is None:
-        had_running_loop = False
-        try:
-            loop = asyncio.get_event_loop()
-        except RuntimeError:
-            # we can still get 'There is no current event loop in ...'
-            loop = asyncio.new_event_loop()
-            asyncio.set_event_loop(loop)
-    else:
-        had_running_loop = True
-    if had_running_loop:
+    if loop is not None:
         # if there is a running loop, we patch using nest_asyncio
         # to have reentrant event loops
         check_ipython()
         import nest_asyncio
         nest_asyncio.apply()
         check_patch_tornado()
-    return loop.run_until_complete(coro)
+        return loop.run_until_complete(coro)
+
+    elif hasattr(asyncio, 'run'):  # Python 3.7 +
+        return asyncio.run(coro)
+
+    else:  # Python 3.6
+        try:
+            loop = asyncio.get_event_loop()
+        except RuntimeError:
+            # we can still get 'There is no current event loop in ...'
+            loop = asyncio.new_event_loop()
+            asyncio.set_event_loop(loop)
+        try:
+            return loop.run_until_complete(coro)
+        finally:
+            loop.close()
 
 
 def run_sync(coro: Callable) -> Callable:

From 8b6ea2dab70fe9253757573ee52ad0bf5680c5cb Mon Sep 17 00:00:00 2001
From: Thomas Kluyver <thomas@kluyver.me.uk>
Date: Mon, 13 Sep 2021 17:07:15 +0100
Subject: [PATCH 2/2] Use temporary event loop when one is not already running
 in just_run

---
 nbclient/util.py | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

diff --git a/nbclient/util.py b/nbclient/util.py
index bafcb778..7b987e94 100644
--- a/nbclient/util.py
+++ b/nbclient/util.py
@@ -37,7 +37,15 @@ def just_run(coro: Awaitable) -> Any:
     """Make the coroutine run, even if there is an event loop running (using nest_asyncio)"""
     # original from vaex/asyncio.py
     loop = asyncio._get_running_loop()
-    if loop is not None:
+    if loop is None:
+        # Create a temporary event loop
+        loop = asyncio.new_event_loop()
+        try:
+            return loop.run_until_complete(coro)
+        finally:
+            loop.close()
+
+    else:
         # if there is a running loop, we patch using nest_asyncio
         # to have reentrant event loops
         check_ipython()
@@ -46,21 +54,6 @@ def just_run(coro: Awaitable) -> Any:
         check_patch_tornado()
         return loop.run_until_complete(coro)
 
-    elif hasattr(asyncio, 'run'):  # Python 3.7 +
-        return asyncio.run(coro)
-
-    else:  # Python 3.6
-        try:
-            loop = asyncio.get_event_loop()
-        except RuntimeError:
-            # we can still get 'There is no current event loop in ...'
-            loop = asyncio.new_event_loop()
-            asyncio.set_event_loop(loop)
-        try:
-            return loop.run_until_complete(coro)
-        finally:
-            loop.close()
-
 
 def run_sync(coro: Callable) -> Callable:
     """Runs a coroutine and blocks until it has executed.