#17079: merge with 3.3.

Lib/test/test_ctypes.py

 import unittest
 
-from test.support import run_unittest, import_module
+from test.support import import_module
 
 # Skip tests if _ctypes module was not built.
 import_module('_ctypes')
 
 import ctypes.test
 
-def test_main():
+def load_tests(*args):
     skipped, testcases = ctypes.test.get_tests(ctypes.test, "test_*.py", verbosity=0)
     suites = [unittest.makeSuite(t) for t in testcases]
-    run_unittest(unittest.TestSuite(suites))
+    return unittest.TestSuite(suites)
 
 if __name__ == "__main__":
-    test_main()
+    unittest.main()

Misc/NEWS

@@ -896,6 +896,9 @@ Tests
 
 - Issue #16836: Enable IPv6 support even if IPv6 is disabled on the build host.
 
+- Issue #17079: test_ctypes now works with unittest test discovery.
+  Patch by Zachary Ware.
+
 - Issue #17304: test_hash now works with unittest test discovery.
   Patch by Zachary Ware.