Merge pull request jupyter-widgets#3740 from TTianshun/add_comm_manag…

…er_check add comm_manager check
martinRenou · Mar 27, 2023 · 05bdab2 · 05bdab2
2 parents 93a848b + 83e1c9d
commit 05bdab2
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/python/ipywidgets/ipywidgets/__init__.py b/python/ipywidgets/ipywidgets/__init__.py
@@ -45,7 +45,8 @@ def load_ipython_extension(ip):
 def register_comm_target(kernel=None):
     """Register the jupyter.widget comm target"""
     comm_manager = get_comm_manager()
-
+    if comm_manager is None:
+        return
     comm_manager.register_target('jupyter.widget', Widget.handle_comm_opened)
     comm_manager.register_target('jupyter.widget.control', Widget.handle_control_comm_opened)