1 files changed, 6 insertions, 1 deletions
diff --git a/Lib/importlib/_bootstrap.py b/Lib/importlib/_bootstrap.py
index 8de0e9e..7b74e88 100644
--- a/Lib/importlib/_bootstrap.py
+++ b/Lib/importlib/_bootstrap.py
@@ -978,7 +978,12 @@ def _find_and_load_unlocked(name, import_):
     if parent:
         # Set the module as an attribute on its parent.
         parent_module = sys.modules[parent]
-        setattr(parent_module, name.rpartition('.')[2], module)
+        child = name.rpartition('.')[2]
+        try:
+            setattr(parent_module, child, module)
+        except AttributeError:
+            msg = f"Cannot set an attribute on {parent!r} for child module {child!r}"
+            _warnings.warn(msg, ImportWarning)
     return module