diff --git a/Lib/_dummy_thread.py b/Lib/_dummy_thread.py
index e03905c2037..7aa6579efe4 100644
--- a/Lib/_dummy_thread.py
+++ b/Lib/_dummy_thread.py
@@ -17,7 +17,6 @@
            'interrupt_main', 'LockType']
 
 import traceback as _traceback
-import warnings
 
 class error(Exception):
     """Dummy implementation of _thread.error."""
diff --git a/Lib/filecmp.py b/Lib/filecmp.py
index 68a8321decb..6dcebaa23df 100644
--- a/Lib/filecmp.py
+++ b/Lib/filecmp.py
@@ -11,7 +11,6 @@
 
 import os
 import stat
-import warnings
 from itertools import filterfalse
 
 __all__ = ["cmp","dircmp","cmpfiles"]
diff --git a/Lib/shelve.py b/Lib/shelve.py
index c8d9cf52947..cf6dac65f47 100644
--- a/Lib/shelve.py
+++ b/Lib/shelve.py
@@ -60,7 +60,6 @@
 from io import BytesIO
 
 import collections
-import warnings
 
 __all__ = ["Shelf","BsdDbShelf","DbfilenameShelf","open"]