Remove two unneeded imports in 'io'.
diff --git a/Lib/io.py b/Lib/io.py
index f90a2f8..8462dd5 100644
--- a/Lib/io.py
+++ b/Lib/io.py
@@ -59,10 +59,8 @@
 
 import os
 import abc
-import sys
 import codecs
 import _fileio
-import warnings
 import threading
 
 # open() uses st_blksize whenever we can
diff --git a/Misc/NEWS b/Misc/NEWS
index 99414d1..d1390cd 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -48,6 +48,8 @@
 Library
 -------
 
+- Remove unneeded imports of 'sys' and 'warnings' from 'io'.
+
 - Remove unneeded imports of 'warnings' from shelve, filecmp, and dummy_thread.
 
 - Issue #3575: Incremental decoder's decode function now takes bytearray