diff --git a/Lib/warnings.py b/Lib/warnings.py
index b05a08e..3822361 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -144,8 +144,8 @@
         module = category[:i]
         klass = category[i+1:]
         try:
-            m = __import__(module, None, None, [klass])
-        except ImportError:
+            m = __import__(module, fromlist[klass])
+        except ModuleNotFoundError:
             raise _OptionError("invalid module name: %r" % (module,))
         try:
             cat = getattr(m, klass)
@@ -362,7 +362,7 @@
     defaultaction = _defaultaction
     onceregistry = _onceregistry
     _warnings_defaults = True
-except ImportError:
+except ModuleNotFoundError:
     filters = []
     defaultaction = "default"
     onceregistry = {}